FN Thomson Reuters Web of Science™ VR 1.0 PT J AU Wu, HB Wang, LS AF Wu, HB Wang, LS TI A photoelectron spectroscopic study of monovanadium oxide anions (VOx-, x=1-4) SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID ELECTRONIC-STRUCTURE; VANADIUM-OXIDE; AB-INITIO; TRANSITION; CLUSTERS; STATE; PERTURBATIONS; MATRICES; BAND AB We report on a photoelectron spectroscopic study of monovanadium oxides, VOx- (x = 1-4), at four photon energies: 532, 355, 266, and 193 nm. Vibrationally resolved spectra are obtained for VO- at 532 and 355 nm detachment photon energies. Two new low-lying excited states are observed for VO at 5630 and 14 920 cm(-1) above the ground state. These states are assigned to two doublet states, (2) Sigma(-) and (2) Phi, respectively. The 532 and 355 nm spectra of VO2- reveal a single vibrational progression for the ground state with a frequency of 970 cm(-1) (nu(1)). Three electronic excited states are observed for VO2 in the 193 nm spectrum. For VO3-, three surprisingly sharp detachment transitions are observed at 193 nm, The two excited states of VO3 are measured to be 0.59 and 0.79 eV above the ground state. The spectra of VO2- and VO3 are interpreted using the molecular-orbital schemes obtained in a recent ab initio theoretical study [Knight, Jr, et al., J. Chem. Phys. 105, 10237 (1996)], which predicts that both VO2 and VO3 neutrals are of C-2 upsilon symmetry with a doublet ground state. The spectrum of VO4- is obtained at 193 nm, showing features similar to that of VO;, but much more broadened, The adiabatic electron affinities of VO, VO2, VO3, and VO4 are measured to be 1.229 (8), 2.03 (1), 4.36 (5), and 4.0 (1) eV, respectively, with a significant increase from VO2 to VO3. The electronic and geometrical structures of the series of monovanadium oxide species are discussed based on the current observation and previous spectroscopic and theoretical results. (C) 1998 American Institute of Physics. [S0021-9606(98)01813-3]. C1 Washington State Univ, Dept Phys, Richland, WA 99352 USA. Pacific NW Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. RP Wu, HB (reprint author), Washington State Univ, Dept Phys, Richland, WA 99352 USA. NR 40 TC 90 Z9 90 U1 2 U2 17 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 1998 VL 108 IS 13 BP 5310 EP 5318 DI 10.1063/1.475966 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZD913 UT WOS:000072738000021 ER PT J AU Blank, DA Sun, WZ Suits, AG Lee, YT North, SW Hall, GE AF Blank, DA Sun, WZ Suits, AG Lee, YT North, SW Hall, GE TI Primary and secondary processes in the 193 nm photodissociation of vinyl chloride SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID UNIMOLECULAR DISSOCIATION REACTIONS; ULTRAVIOLET PHOTODISSOCIATION; EMISSION-SPECTROSCOPY; DOPPLER PROFILES; CHLOROETHYLENES; DYNAMICS; DISTRIBUTIONS; DEPENDENCE; HCL; CL AB We have investigated the photodissociation of vinyl chloride (H2CCHCl) at 193 nm using the technique of photofragment translational spectroscopy, The experiments were performed at the Chemical Dynamics Beamline at the Advanced Light Source and used vacuum ultraviolet synchrotron radiation for product photoionization. We have observed five primary dissociation channels following an initial pi*<--pi excitation. The majority of Cl atoms originate from an excited-state dissociation. The remaining dissociation channels are consistent with competition on the ground electronic state following internal conversion from the optically prepared state, These channels include atomic and molecular hydrogen elimination, HCl elimination, and a translationally slow Cl elimination channel. We have also identified and characterized two secondary decomposition channels: (1) the elimination of Cl from chlorovinyl radicals following the primary atomic hydrogen elimination channel, and (2) hydrogen atom elimination from vinyl radicals following the primary atomic Cl elimination, By measuring the truncation in the translational energy distribution for C2H2Cl products from primary atomic hydrogen elimination we deduce a barrier for the reverse reaction of Cl+acetylene of 11+/-2kcal/mol, Since Cl is known to add rapidly to acetylene with no activation barrier, we conclude that H loss primarily forms the ClCCH2 isomer, and that the observed 11 kcal/mol barrier pertains to a concerted addition/rearrangement path to form the alpha-chlorovinyl radical. Finally, we report low-resolution photoionization spectra for the nascent vinyl radical and HCl photoproducts, in which redshifts in the ionization onsets can be related to the internal energy content. (C) 1998 American Institute of Physics. [S0021-9606(98)02313-7]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Blank, DA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RI Lee, Yuan-Tseh/F-7914-2012; North, Simon/G-5054-2012; Hall, Gregory/D-4883-2013 OI North, Simon/0000-0002-0795-796X; Hall, Gregory/0000-0002-8534-9783 NR 43 TC 93 Z9 93 U1 0 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 1998 VL 108 IS 13 BP 5414 EP 5425 DI 10.1063/1.475930 PG 12 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZD913 UT WOS:000072738000030 ER PT J AU Lue, L Prausnitz, JM AF Lue, L Prausnitz, JM TI Renormalization-group corrections to an approximate free-energy model for simple fluids near to and far from the critical region SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID EQUILIBRIUM STATISTICAL MECHANICS; THERMODYNAMIC PROPERTIES; DIFFERENTIAL APPROACH; CRITICAL-BEHAVIOR; CRITICAL-POINT; GENERAL THEORY; EXPANSION; MIXTURES; METHANE; LIQUID AB We combine liquid-state theory with a renormalization-group method to develop an equation of state for simple fluids that is valid near and far from the critical point. The resulting equation of state has nonclassical critical exponents close to those experimentally observed. Far away from the critical point, the equation of state reduces to that obtained by liquid-state theory. This formalism is applied successfully to square-well fluids, and to three real fluids: methane, carbon dioxide, and n-butane. (C) 1998 American Institute of Physics. [S0021-9606(98)50713-1]. C1 Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Prausnitz, JM (reprint author), Univ Calif Berkeley, Dept Chem Engn, Berkeley, CA 94720 USA. RI Lue, Leo/E-7846-2011 OI Lue, Leo/0000-0002-4826-5337 NR 42 TC 65 Z9 67 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 1998 VL 108 IS 13 BP 5529 EP 5536 DI 10.1063/1.475942 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZD913 UT WOS:000072738000043 ER PT J AU Frink, LJD van Swol, F AF Frink, LJD van Swol, F TI Solvation forces between rough surfaces SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DENSITY-FUNCTIONAL THEORY; FLUID-WALL INTERFACE; HARD-SPHERE FLUID; COMPUTER-SIMULATION; DRYING TRANSITIONS; ADSORPTION; LIQUID; ENERGY; ADHESION; LINE AB We investigate the role of surface roughness on solvation forces and solvation free energies. Roughness is introduced by dividing a surface into an array of square tiles that are then randomly displaced in the direction perpendicular to the wall. The integrated wall strength of these tiled surfaces is independent of the surface roughness and hence this class of rough walls is ideally suited for isolating roughness effects. We use grand canonical Monte Carlo simulations of a Lennard-Jones fluid confined in a slit pare with rough walls to generate the solvation interactions as a function of roughness, the size, and surface area. The simulation data ate compared to a simple superposition approximation of smooth wall solvation interactions (obtained from simulation or density functional theory), based on a distribution of wall separations. We find that this approximation provides a surprisingly accurate route to the solvation interaction of rough surfaces. In general, increased roughness leads to a reduction of oscillations in the solvation forces and surface free energies. However, nonmonotonic behavior of the oscillation amplitude with roughness can be observed for finite surfaces. The washing out of the oscillations found for large surface roughness produces a solvation force that exhibits a broad repulsive peak with separation. The broad repulsion is a consequence of the resistance to squeezing out fluid from the smallest gaps between two opposing rough surfaces, It is as much a reflection of packing effects as are the solvation oscillations for perfectly smooth pores. In addition, we present results for patterned and undulating surfaces produced by an analogous modification of the one-body external field for smooth walls. Finally, we discuss the implications of our results for a number of experimental systems including self-assembled monolayers, microporous materials, protein solutions, and DNA crystals. (C) 1998 American Institute of Physics. [S0021-9606(97)50213-3]. C1 Sandia Natl Labs, Dept 9225, Albuquerque, NM 87185 USA. RP Frink, LJD (reprint author), Sandia Natl Labs, Dept 9225, POB 5800, Albuquerque, NM 87185 USA. NR 27 TC 53 Z9 53 U1 0 U2 13 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 1998 VL 108 IS 13 BP 5588 EP 5598 DI 10.1063/1.475973 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZD913 UT WOS:000072738000050 ER PT J AU Kent, MS Majewski, J Smith, GS Lee, LT Satija, S AF Kent, MS Majewski, J Smith, GS Lee, LT Satija, S TI Tethered chains in theta solvent conditions: An experimental study involving Langmuir diblock copolymer monolayers SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GRAFTED POLYMERIC BRUSHES; NEUTRON REFLECTIVITY; MOLECULAR-DYNAMICS; DENSITY PROFILE; POOR SOLVENTS; MONTE-CARLO; LAYERS; TRANSITION; SIMULATION; COLLAPSE AB Langmuir monolayers of polydimethylsiloxane-polystyrene (PDMS-PS) diblock copolymers on dioctyl phthalate (DOP) at 22 degrees C are employed as a model tethered chain system in theta solvent conditions. The segmental concentration profile of the tethered PS block is obtained over an order of magnitude in both surface density (sigma) and molecular weight (M) by neutron reflection. A depletion layer of PS segments is observed at the air-liquid interface which increases with M and is independent of sigma. The variation of the tethered layer height with sigma and M is consistent with h similar to sigma(0.18)M(0.74) over the range of reduced surface density (sigma pi R-g(2)) from 1 to 11. These dependencies, along with the form of the profile, indicate that the asymptotic limit is not achieved for sigma pi R-g(2) less than or equal to 11 in theta solvent conditions. The upper limit of surface density is limited by the interaction of the submerged blocks, which leads to a sharp rise in surface pressure (Pi). The increase of Pi with sigma far exceeds theoretical predictions, even in the asymptotic limit, and is attributed to distortion of chain configurations arising from limited lateral interpenetration. Anchoring energies compare well with differential chain energies at the desorption transition when the surface PDMS blocks an noninteracting. Comparisons are made with results obtained previously in good solvent conditions. (C) 1998 American Institute of Physics. [S0021-9606(98)50110-9]. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. CENS, Lab Leon Brillouin, F-91191 Gif Sur Yvette, France. Natl Inst Stand & Technol, Ctr Nutr Res, Gaithersburg, MD 20899 USA. RP Kent, MS (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Lujan Center, LANL/G-4896-2012 NR 52 TC 29 Z9 29 U1 1 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD APR 1 PY 1998 VL 108 IS 13 BP 5635 EP 5645 DI 10.1063/1.475952 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZD913 UT WOS:000072738000055 ER PT J AU Barnett, TP Hegerl, GC Santer, B Taylor, K AF Barnett, TP Hegerl, GC Santer, B Taylor, K TI The potential effect of GCM uncertainties and internal atmospheric variability on anthropogenic signal detection SO JOURNAL OF CLIMATE LA English DT Article ID FORCED CLIMATE SIGNALS; FINGERPRINT DETECTION; MODEL; TEMPERATURE; PREDICTABILITY; CIRCULATION; TROPOSPHERE; AMIP AB When long integrations of climate models forced by observed boundary conditions are compared against observations, differences appear that have spatial and temporal coherence. These differences are due to several causes, the largest of which are fundamental model errors and the internal variability inherent in a GCM integration. Uncertainties in the observations themselves are small in comparison. The present paper constitutes a first attempt to compare the time dependence of these spatial difference patterns with the time dependence of simulated spatial patterns of climate change associated with anthropogenic sources. The analysis procedure was to project the model minus observed near-surface temperature difference fields onto estimates of the anthropogenic "signal" tin this case the response to greenhouse-gas and sulfate-aerosol forcing). The temporal behavior of this projection was then compared with the estimated temporal evolution of the anthropogenic signal. Such comparisons were performed on timescales of 10, 20, and 30 yr. For trends of only 10 yr in length, the model minus observed spatial difference patterns are of the same magnitude and have the same time rate of change as the expected anthropogenic signal. In the case of 20-and 30-yr trends, the prospects are favorable for discriminating between temperature changes due to anthropogenic signal changes and changes associated with model minus observed difference structures. This suggests that attempts to quantitatively detect anthropogenic climate change should be based on temporal samples of at least several decades in length. This study also shows the importance of distinguishing between purely statistical detection and what the authors term practical prediction. It is found that the results of the detection analysis are sensitive to the spatial resolution at which it is performed: for the specific case of near-surface temperature, higher spatial resolution improves ability to discriminate between an anthropogenic signal and the type of model error/internal variability "noise" considered here. C1 Univ Calif San Diego, Scripps Inst Oceanog, Dept 0224, La Jolla, CA 92093 USA. Max Planck Inst Meteorol, Hamburg, Germany. Univ Calif Lawrence Livermore Natl Lab, Program Climate Model Diag & Intercomparis, Livermore, CA USA. RP Barnett, TP (reprint author), Univ Calif San Diego, Scripps Inst Oceanog, Dept 0224, 9500 Gilman Dr, La Jolla, CA 92093 USA. RI Taylor, Karl/F-7290-2011; Santer, Benjamin/F-9781-2011 OI Taylor, Karl/0000-0002-6491-2135; NR 42 TC 11 Z9 11 U1 1 U2 5 PU AMER METEOROLOGICAL SOC PI BOSTON PA 45 BEACON ST, BOSTON, MA 02108-3693 USA SN 0894-8755 J9 J CLIMATE JI J. Clim. PD APR PY 1998 VL 11 IS 4 BP 659 EP 675 DI 10.1175/1520-0442(1998)011<0659:TPEOGU>2.0.CO;2 PG 17 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZK575 UT WOS:000073338900012 ER PT J AU Blum, A Chalasani, P Goldman, SA Slonim, DK AF Blum, A Chalasani, P Goldman, SA Slonim, DK TI Learning with unreliable boundary queries SO JOURNAL OF COMPUTER AND SYSTEM SCIENCES LA English DT Article; Proceedings Paper CT 8th Annual Conference on Computational Learning Theory CY JUL 05-08, 1995 CL SANTA CRUZ, CA ID NOISE; LEARNABILITY; EQUIVALENCE; ALGORITHMS; FORMULAS; MODELS AB We introduce a model for learning from examples and membership queries in situations where the boundary between positive and negative examples is somewhat iii-defined. In our model, queries near the boundary of a target concept may receive incorrect or "don't care" responses, and the distribution of examples has zero probability mass on the boundary region. The motivation behind our model is that in many cases the boundary between positive and negative examples is complicated or "fuzzy." However, one may still hope to learn successfully, because the typical examples that one sees do not come from that region, We present several positive results in this new model. We show how to learn the intersection of two arbitrary halfspaces when membership queries near the boundary may be answered incorrectly. Our algorithm is an extension of an algorithm of Baum (1990, 1991) that learns the intersection of two halfspaces whose bounding planes pass through the origin in the PAC-with-membership-queries model. We also describe algorithms for reaming several subclasses of monotone DNF formulas. (C) 1998 Academic Press. C1 Carnegie Mellon Univ, Sch Comp Sci, Pittsburgh, PA 15213 USA. Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Washington Univ, Dept Comp Sci, St Louis, MO 63130 USA. MIT, Ctr Genome Res, Cambridge, MA 02139 USA. RP Blum, A (reprint author), Carnegie Mellon Univ, Sch Comp Sci, Pittsburgh, PA 15213 USA. EM avrim@theory.cs.cmu.edu; chal@lanl.gov; sg@cs.wustl.edu; slonim@genome.wi.mit.edu NR 30 TC 8 Z9 8 U1 0 U2 0 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-0000 EI 1090-2724 J9 J COMPUT SYST SCI JI J. Comput. Syst. Sci. PD APR PY 1998 VL 56 IS 2 BP 209 EP 222 DI 10.1006/jcss.1997.1559 PG 14 WC Computer Science, Hardware & Architecture; Computer Science, Theory & Methods SC Computer Science GA ZW502 UT WOS:000074417400006 ER PT J AU Gerard, F Clement, A Fritz, B AF Gerard, F Clement, A Fritz, B TI Numerical validation of a Eulerian hydrochemical code using a 1D multisolute mass transport system involving heterogeneous kinetically controlled reactions SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article ID FLUID-ROCK INTERACTION; POROUS-MEDIUM; DIFFUSION; SOILS; PRECIPITATION; DISSOLUTION; DISPERSION; FRACTURE; MODELS; FLOW AB It is demonstrated that at steady state, the ID thermo-kinetic hydrochemical Eulerian mass balance equations in pure advective mode are indeed identical to the governing mass balance equations of a single reaction path (or geochemical) code in open system mode. Thus, both calculated reaction paths should be theoretically identical whatever the chemical complexity of the water-rock system (i.e., multicomponent, multireaction zones kinetically and equilibrium-controlled). We propose to use this property to numerically test the thermo-kinetic hydrochemical Eulerian codes and we employ it to verify the algorithm of the 1D finite difference code KIRMAT. Compared to the other methods to perform such numerical tests (i.e., comparisons with analytical, semi-analytical solutions, between two Eulerian hydrochemical codes), the advantage of this new method is the absence of constraints on the chemical complexity of the modelled water-rock systems. Moreover, the same thermo-kinetic databases and geochemical functions can be easily and mechanically used in both calculations, when the numerical reference comes from the Eulerian code with no transport terms (u and D = 0) and modify to be consistent with the definition of the open system mode in geochemical modelling. The ability of KIRMAT to treat multicomponent pure advective transport, subjected to several kinetically equilibrium-controlled dissolution and precipitation reactions, and to track their boundaries has been successfully verified with the property of interest. The required numerical validation of the reference calculations is bypassed in developing the Eulerian code from an already checked single reaction path code. A forward time-upstream weighting scheme (a mixing cell scheme) is used in this study. An appropriate choice of grid spacing allows to calculate within the grid size uncertainty the correct mineral reaction zone boundaries, despite the presence of numerical dispersion. Its correction enables us to improve the convergence and to extend the numerical test to mixed advective-dispersive mass transport. However, the skewness factor involves numerical oscillations that prevent to compute different grid spacing. The use of a different chemically controlled time step constraint in both calculations induces some inconsistencies into the validation tests. This numerical validation method may be applied as well as to check a thermo-kinetic hydrochemical finite element based code, from a 1D heterogeneous systems, and 2D-3D systems provided that they are designed so as to be 1D equivalent. A one-step algorithm and the use of a numerical reference coming from the Eulerian code to be tested ensure the potential success (accuracy) of the numerical validation method. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Dept Geol & Geophys, Earth Resources Ctr, Berkeley, CA 94720 USA. CNRS, Ctr Geochim Surface, UPR 6251, F-67084 Strasbourg, France. RP Gerard, F (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. NR 29 TC 13 Z9 13 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD APR PY 1998 VL 30 IS 3-4 BP 201 EP 216 DI 10.1016/S0169-7722(97)00047-8 PG 16 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZP465 UT WOS:000073756200001 ER PT J AU Yabusaki, SB Steefel, CI Wood, BD AF Yabusaki, SB Steefel, CI Wood, BD TI Multidimensional, multicomponent, subsurface reactive transport in nonuniform velocity fields: code verification using an advective reactive streamtube approach SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article ID STOCHASTIC-CONVECTIVE TRANSPORT; SOLUTE TRANSPORT; POROUS-MEDIA; MASS-TRANSPORT; HYDROTHERMAL SYSTEMS; NONLINEAR REACTION; CHEMICAL-REACTIONS; MODEL DEVELOPMENT; FLUID-FLOW; SOIL AB High performance computing has made possible the development of high resolution, multidimensional, multicomponent reactive transport models that can be used to analyze complex geochemical environments. However, as increasingly complex processes are included in these models, the accuracy of the numerical formulation coupling the nonlinear processes becomes difficult to verify. Analytical solutions are not available for realistically complex problems and benchmark solutions are not generally available for specific problems. We present an advective reactive streamtube (ARS) transport technique that efficiently provides accurate solutions of nonlinear multicomponent reactive transport in nonuniform multidimensional velocity fields. These solutions can be compared with results from Eulerian-based advection-dispersion-reaction models to evaluate the accuracy of the numerical formulation used. The ARS technique includes mixed equilibrium and kinetic complexation and precipitation-dissolution reactions subject to the following assumptions: (1) transport is purely advective (i.e., no explicit diffusion or dispersion), and (2) chemistry is described by a canonical system of reactions that evolves with time and is unaffected by position in space. Results from the ARS technique are compared with results from the massively parallel, multicomponent reactive transport model MCTRACKER on a test problem involving irreversible oxidation of organic carbon and reaction of the oxidation products with two immobile mineral phases, gypsum and calcite, and fifteen aqueous complexes. Truncation error, operator splitting error, and the nonlinear transformation of these errors in the high-resolution reactive transport model are identified for this problem. (C) 1998 Elsevier Science B.V. C1 Pacific NW Natl Lab, Richland, WA 99352 USA. Univ S Florida, Dept Geol, Tampa, FL 33620 USA. Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA USA. RP Yabusaki, SB (reprint author), Pacific NW Natl Lab, Richland, WA 99352 USA. RI Steefel, Carl/B-7758-2010; Wood, Brian/K-4025-2012; Wood, Brian/J-8362-2013 OI Wood, Brian/0000-0003-3152-7852; Wood, Brian/0000-0003-3152-7852 NR 44 TC 31 Z9 31 U1 2 U2 11 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD APR PY 1998 VL 30 IS 3-4 BP 299 EP 331 DI 10.1016/S0169-7722(97)00050-8 PG 33 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZP465 UT WOS:000073756200006 ER PT J AU Pruess, K AF Pruess, K TI On water seepage and fast preferential flow in heterogeneous, unsaturated rock fractures SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article ID SANDY VADOSE ZONE; THERMOHYDROLOGIC CONDITIONS; RELATIVE PERMEABILITY; POROUS-MEDIUM; FLUID-FLOW; MODEL; INFILTRATION; TUFF AB Evidence from a number of field sites suggests that water seepage through fractured unsaturated zones may proceed, in part, by means of fast preferential flow paths. This paper presents conceptual and numerical models which aim at developing an understanding of water seepage behavior in such media, and exploring conditions for fast preferential flow. Water seepage has been numerically simulated in heterogeneous fractures, which were conceptualized as two-dimensional heterogeneous porous media. Flow was found to proceed in dendritic patterns along preferential paths, giving rise to such features as localized pending and bypassing. Fast preferential flow can occur from 'external' (non-uniform boundary conditions) or 'internal' mechanisms (heterogeneities), or a combination thereof. A most effective condition for fast preferential flow is the presence of sub-horizontal barriers of significant length. Limited parameter variation studies have shown strong dependence of seepage patterns on fracture permeability and applied flow rate. The temporal evolution of seeps proceeds on a vast range of time scales. This casts doubt on the applicability of steady-state concepts for water migration in unsaturated zones of fractured rock where infiltration is episodic. An approximate invariance of seepage behavior was derived for simultaneous space-and-time scaling, suggesting that seepage patterns should appear more vertically elongated as the scale of observation is increased. Numerical simulation experiments have confirmed this invariance, as well as its limits of applicability. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. RP Pruess, K (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. NR 49 TC 33 Z9 36 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD APR PY 1998 VL 30 IS 3-4 BP 333 EP 362 DI 10.1016/S0169-7722(97)00049-1 PG 30 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZP465 UT WOS:000073756200007 ER PT J AU Cho, H Vartuli, CB Donovan, SM Mackenzie, JD Abernathy, CR Pearton, SJ Shul, RJ Constantine, C AF Cho, H Vartuli, CB Donovan, SM Mackenzie, JD Abernathy, CR Pearton, SJ Shul, RJ Constantine, C TI Low bias dry etching of III-nitrides in Cl-2-based inductively coupled plasmas SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, COLORADO HO COLORADA STATE UNIV DE III-V nitrides; Cl-2 discharges; dry etching ID FIELD-EFFECT TRANSISTORS; MOLECULAR-BEAM EPITAXY; OHMIC CONTACTS; V NITRIDES; GAN; INP; CL-2/AR; GROWTH; ALN; CL2 AB Cl-2-based inductively coupled plasmas (ICP) with low additional de self-biases (-100V) produce convenient etch rates (500-1500 Angstrom.min(-1)) for III-nitride electronic device structures. A systematic study of the effects of additive gas (Ar, N-2, H-2), discharge composition, process pressure, and ICP source power and chuck power on etch rate and surface morphology has been performed. The general trends are to go through a maximum in etch rate with percent Cl-2 in the discharge for all three mixtures, and to have an increase (decrease) in etch rate with source power (pressure). Since the etching is strongly ion-assisted, anisotropic pattern transfer is readily achieved. Maximum etch selectivities of approximately six for InN over the other nitrides were obtained. C1 Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Lucent Technol, Orlando, FL USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Plasma Therm Inc, St Petersburg, FL 33716 USA. RP Cho, H (reprint author), Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. NR 29 TC 13 Z9 13 U1 2 U2 11 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 166 EP 170 DI 10.1007/s11664-998-0380-0 PG 5 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600003 ER PT J AU Ren, F Pearton, SJ Shul, RJ Han, J AF Ren, F Pearton, SJ Shul, RJ Han, J TI Improved sidewall morphology on dry-etched SiO2 masked GaN features SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, COLORADO HO COLORADA STATE UNIV DE GaN; mask; photoresist; plasmas ID ROUGHNESS; INP AB A number of different methods have been investigated for minimizing sidewall roughness on dry etched GaN features formed using high density plasmas. In many instances, striations on dry etched mesas are a result of roughness in the initial photoresist mask employed, and this roughness is transferred sequentially to the dielectric mask and then to the GaN. Flood exposure of the photoresist, optimization of the bake temperature, choice of plasma chemistry, and ion flux/energy for patterning the dielectric mask all influence the final GaN sidewall morphology. C1 AT&T Bell Labs, Lucent Technol, Murray Hill, NJ 07974 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ren, F (reprint author), Univ Florida, Dept Chem Engn, Gainesville, FL 32611 USA. NR 16 TC 11 Z9 11 U1 0 U2 13 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 175 EP 178 DI 10.1007/s11664-998-0382-y PG 4 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600005 ER PT J AU Zolper, JC Han, J Biefeld, RM Van Deusen, SB Wampler, WR Reiger, DJ Pearton, SJ Williams, JS Tan, HH Karlicek, RF Stall, RA AF Zolper, JC Han, J Biefeld, RM Van Deusen, SB Wampler, WR Reiger, DJ Pearton, SJ Williams, JS Tan, HH Karlicek, RF Stall, RA TI Si-implantation activation annealing of GaN up to 1400 degrees C SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, CO HO COLORADA STATE UNIV DE AlN; annealing; GaN; ion implantation ID TRANSISTOR; DOPANTS; ALN AB Implant activation annealing of Si-implanted GaN is reported for temperatures from 1100 to 1400 degrees C. Free electron concentrations up to 3.5 x 10(20) cm(-3) are estimated at the peak of the implanted profile with Hall mobilities of similar to 60 cm(2)/Vs for annealing at 1300 degrees C for 30 s with an AIN encapsulant layer. This mobility is comparable to epitaxial GaN doped at a similarly high level. For annealing at greater than or equal to 1300 degrees C, the sample must be encapsulated with AIN to prevent decomposition of the GaN layer. Channeling Rutherford backscattering demonstrates the partial removal of the implant damage after a 1400 degrees C anneal with a minimum channeling yield of 12.6% compared to 38.6% for the as-implanted spectrum. Scanning electron microscope images show evidence of decomposition of unencapsulated GaN after a 1300 degrees C anneal and complete sublimation after 1400 degrees C. The use of AIN encapsulation and annealing at temperatures of similar to 1300 degrees C will allow the formation of selective areas of highly doped GaN to reduce the contact and access resistance in GaN-based transistors and thyristors. C1 US Off Naval res, Arlington, VA 22217 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Australian Natl Univ, Dept Elect Mat Engn, Canberra, ACT 0200, Australia. EMCORE Corp, Somerset, NJ 08873 USA. RP US Off Naval res, Arlington, VA 22217 USA. RI Tan, Hark Hoe/M-1148-2015 OI Tan, Hark Hoe/0000-0002-7816-537X NR 22 TC 28 Z9 28 U1 0 U2 4 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0361-5235 EI 1543-186X J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 179 EP 184 DI 10.1007/s11664-998-0383-x PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600006 ER PT J AU Ng, TB Han, J Biefeld, RM Weckwerth, MV AF Ng, TB Han, J Biefeld, RM Weckwerth, MV TI In-situ reflectance monitoring during MOCVD of AlGaN SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, COLORADO HO COLORADA STATE UNIV DE AlGaN; in-situ; metalorganic chemical vapor deposition (MOCVD); reflectance ID CHEMICAL-VAPOR-DEPOSITION; MOLECULAR-BEAM EPITAXY; BUFFER LAYER; LIGHT-SCATTERING; GAN; GROWTH; SAPPHIRE; TEMPERATURE; FILMS; FLOW AB We report in-situ optical reflectance monitoring during the metalorganic chemical vapor deposition (MOCVD) growth of(AI)GaN. In addition to the well-known thin film interference effect which enables a real-time determination of growth rate, we show that several insights about the MOCVD growth process can be gained by using this simple yet powerful technique. Illustrations from a variety of applications for in-situ reflectance monitoring, specifically the study of growth evolution, the control of alloy fractions, and the use of growth rate to gauge surface kinetics and gas injection will be reported. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Star Med Technol, Pleasanton, CA 94566 USA. RP Ng, TB (reprint author), Sandia Natl Labs, Albuquerque, NM 87185 USA. NR 30 TC 33 Z9 33 U1 0 U2 9 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 190 EP 195 DI 10.1007/s11664-998-0385-8 PG 6 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600008 ER PT J AU Sudhir, GS Fujii, H Wong, WS Kisielowski, C Newman, N Dieker, C Liliental-Weber, Z Rubin, MD Weber, ER AF Sudhir, GS Fujii, H Wong, WS Kisielowski, C Newman, N Dieker, C Liliental-Weber, Z Rubin, MD Weber, ER TI Control of the structure and surface morphology of gallium nitride and aluminum nitride thin films by nitrogen background pressure in pulsed laser deposition SO JOURNAL OF ELECTRONIC MATERIALS LA English DT Article; Proceedings Paper CT 39th Electronic Materials Conference (EMC) CY 1997 CL COLORADA STATE UNIV, FT COLLINS, COLORADO HO COLORADA STATE UNIV DE AlN; doping; GaN; lattice parameter; pulsed laser deposition (PLD) ID BUFFER LAYER; EPITAXIAL-GROWTH; GAN; SAPPHIRE AB Thin films of AIN and GaN were grown by pulsed laser deposition on c-plane sapphire substrates. It is demonstrated that the structure and surface morphology of layers can actively be controlled by adjusting the nitrogen partial pressure during the growth. The observed trends in the structural quality of the thin films can be attributed to the changes in the surface diffusion of adatoms. It is argued that the surface diffusion of adatoms can be influenced by the collisions between the nitrogen gas molecules and the activated atoms which can reduce the kinetic energy of activated atoms and increase the rate of formation of immobile surface dimers. Through these nitrogen pressure related effects, thin films with microstructure ranging from crystalline to amorphous can be produced. The observed similar impact of nitrogen pressure on the growth of GaN and AIN thin films indicates that a pressure assisted growth procedure is generally applicable to design the surface morphology of group III-nitride thin films. A minimal surface root mean square roughness of 0.7 nm for amorphous AIN is obtained which compares well with the substrate roughness of 0.5 nm. Rutherford backscattering spectroscopy of thin films of GaN and AIN showed a large incorporation of oxygen which was found to reduce the lattice constants of GaN and AIN. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Northwestern Univ, Dept Elect & Comp Engn, Evanston, IL 60208 USA. Lawrence Berkeley Lab, Berkeley, CA USA. RP Sudhir, GS (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. RI Newman, Nathan/E-1466-2011; Liliental-Weber, Zuzanna/H-8006-2012 OI Newman, Nathan/0000-0003-2819-9616; NR 15 TC 10 Z9 11 U1 1 U2 10 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 0361-5235 J9 J ELECTRON MATER JI J. Electron. Mater. PD APR PY 1998 VL 27 IS 4 BP 215 EP 221 DI 10.1007/s11664-998-0390-y PG 7 WC Engineering, Electrical & Electronic; Materials Science, Multidisciplinary; Physics, Applied SC Engineering; Materials Science; Physics GA ZJ744 UT WOS:000073248600013 ER PT J AU Richards, GA Janus, MC AF Richards, GA Janus, MC TI Characterization of oscillations during premix gas turbine combustion SO JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER-TRANSACTIONS OF THE ASME LA English DT Article; Proceedings Paper CT 42nd International Gas Turbine and Aeroengine Congress and Exhibition CY JUN 02-05, 1997 CL ORLANDO, FLORIDA SP Int Gas Turbine Inst ID PULSE AB The use of premix combustion in stationary gas turbines can produce very low levels of NOx emissions. This benefit is widely recognized but turbine developers routinely encounter problems with combustion oscillations during the testing of new premix combustors. Because of the associated pressure fluctuations, combustion oscillations must be eliminated in a final combustor design. Eliminating these oscillations is often time-consuming and costly because there is no single approach to solve an oscillation problem, Previous investigations of combustion stability have focused on rocket applications, industrial furnaces, and some aeroengine gas turbines. Comparatively little published data is available for premixed combustion at conditions typical of an industrial gas turbine. In this paper we report experimental observations of oscillations produced by a fuel nozzle typical of industrial gas turbines. Tests are conducted in a specially designed combustor capable of providing the acoustic feedback needed to study oscillations. Tests results are presented for pressures lip to IO atmospheres, with inlet air temperatures up to 588 K (600 F) burning natural gas fuel. Based on theoretical considerations, it is expected that oscillations can be characterized by a nozzle reference velocity, with operating pressure playing a smaller role. This expectation is compared to observed data that shows both the benefits and limitations of characterizing the combustor oscillating behavior in terms of a reference velocity rather than other engine operating parameters. This approach to characterizing oscillations is then used to evaluate how geometric changes to the fuel nozzle will affect the boundary between stable and oscillating combustion. C1 Fed Energy Technol Ctr, Morgantown, WV 26507 USA. RP Janus, MC (reprint author), Fed Energy Technol Ctr, 3610 Collins Ferry Rd, Morgantown, WV 26507 USA. NR 31 TC 74 Z9 77 U1 1 U2 9 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0742-4795 J9 J ENG GAS TURB POWER JI J. Eng. Gas. Turbines Power-Trans. ASME PD APR PY 1998 VL 120 IS 2 BP 294 EP 302 DI 10.1115/1.2818120 PG 9 WC Engineering, Mechanical SC Engineering GA ZM040 UT WOS:000073498700008 ER PT J AU Lara-Curzio, E AF Lara-Curzio, E TI Oxidation induced stress - Rupture of fiber bundles SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID STRENGTH AB The effect of oxidation on the stress-rupture behavior of fiber bundles was modeled. If is shown that oxidation-induced fiber strength degradation results in the delayed failure of the associated fiber bundle and that the fiber bundle strength decreases with time as t(-1/4). It is also shown that the temperature dependence of the bundle loss of strength reflects the thermal dependence of the mechanism controlling the oxidation of the fibers. The effect of gauge length on the fiber bundle strength,vas also analyzed. Numerical examples are presented for the special case of Nicalon (TM) fibers. C1 Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Lara-Curzio, E (reprint author), Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. NR 11 TC 17 Z9 17 U1 0 U2 1 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD APR PY 1998 VL 120 IS 2 BP 105 EP 109 DI 10.1115/1.2806996 PG 5 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZH686 UT WOS:000073137400002 ER PT J AU Christensen, RM AF Christensen, RM TI The numbers of elastic properties and failure parameters for fiber composites SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article AB It is shown that there is a coordination between the numbers of the elastic properties and the numbers of the failure criteria parameters for aligned fiber composites under certain realistic conditions. These conditions require a high degree of anisotropy appropriate to polymeric matrix composites such that failure decomposes into separate fiber dominated and matrix dominated modes. Failure criteria are given in both five parameter and four parameter forms. The five parameter failure form coordinates with the usual five elastic property form for transversely isotropic composites. The four parameter failure form coordinates with a reduced four elastic property form which is shown to be applicable as an approximation for the same typical fiber composites. C1 Stanford Univ, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Div Mat Sci & Technol, Livermore, CA 94551 USA. RP Christensen, RM (reprint author), Stanford Univ, POB 808,L-355, Livermore, CA 94551 USA. NR 7 TC 30 Z9 31 U1 2 U2 6 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD APR PY 1998 VL 120 IS 2 BP 110 EP 113 DI 10.1115/1.2806997 PG 4 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZH686 UT WOS:000073137400003 ER PT J AU Li, J Thostenson, ET Chou, TW Riester, L AF Li, J Thostenson, ET Chou, TW Riester, L TI An investigation of thin-film coating/substrate systems by nanoindentation SO JOURNAL OF ENGINEERING MATERIALS AND TECHNOLOGY-TRANSACTIONS OF THE ASME LA English DT Article ID DOUBLE-LAYER COATINGS; CONTACT STRESSES; HIGH MODULUS; INDENTATION; ADHESION; DELAMINATION; MECHANICS; ADHERENCE; HARDNESS AB The indentation load-displacement behavior of three material systems tested with a Berkovich indenter has been examined. The materials studied were the substrate materials-silicon and polycarbonate, and the coating/substrate systems--diamond-like carbon (DLC) coating on silicon, and DLC coating on polycarbonate. They represent three material systems, namely, bulk, soft-coating/hard-substrate, and hard-coating on soft-substrate. Delaminations in the soft-coating/hard-substrate (DLC/Si) system and cracking in the hard-coating/soft-substrate system (DLC/Polycarbonate) were observed. Parallel to the experimental work, an elastic analytical effort has been made to examine the influence of the film thickness and the properties of the coating/substrate systems. Comparisons between the experimental data and analytical solutions of the load-displacement curves during unloading show good agreement. The analytical solution also suggests that the Young's modulus and hardness of the thin film can not be measured accurately using Sneddon's solution for bulk materials when the thickness of the film is comparable to the loading contact radius of the indenter. The elastic stress field analysis provides a basis for understanding the experimentally observed delaminations and cracking of the coating/substrate systems. C1 Univ Delaware, Ctr Composite Mat, Newark, DE 19716 USA. Univ Delaware, Dept Mech Engn, Newark, DE 19716 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Li, J (reprint author), Univ Delaware, Ctr Composite Mat, Newark, DE 19716 USA. RI Thostenson, Erik/B-8587-2008 NR 25 TC 6 Z9 6 U1 0 U2 3 PU ASME-AMER SOC MECHANICAL ENG PI NEW YORK PA 345 E 47TH ST, NEW YORK, NY 10017 USA SN 0094-4289 J9 J ENG MATER-T ASME JI J. Eng. Mater. Technol.-Trans. ASME PD APR PY 1998 VL 120 IS 2 BP 154 EP 162 DI 10.1115/1.2807005 PG 9 WC Engineering, Mechanical; Materials Science, Multidisciplinary SC Engineering; Materials Science GA ZH686 UT WOS:000073137400011 ER PT J AU Zuo, QH Hjelmstad, KD AF Zuo, QH Hjelmstad, KD TI Piecewise linear warping theory for multilayered elastic beams SO JOURNAL OF ENGINEERING MECHANICS LA English DT Article AB Warping due to transverse shear in multilayered elastic beams is studied in this paper. The Betnoulli-Kirchhoff hypothesis that plane sections remain plane after deformations, with independent rotations, is assumed for each lamina to account for the out-of-plane deformation of the composite cross section. The effects of shear are included by taking the rotations independent of the transverse deflection, as in Timoshenko beam theory. The result is a simple piecewise linear warping theory for layered composite beams. The solution to the governing equations is presented in terms of the eigenvalues and eigenvectors of a generalized matrix eigenvalue problem associated with the coefficient matrices that appear in the governing equations. The problem of a two-layered cantilever beam subjected to a uniformly distributed loading is solved in detail to show the effects of different elastic moduli on the interfacial shear stress. Compared with a finite-element solution, the current theory yields significant improvement over elementary beam theory (excluding warping) in predicting the interface shear stress. C1 Los Alamos Natl Lab, Div Theoret, Fluid Dyn Grp, Los Alamos, NM 87545 USA. Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. RP Zuo, QH (reprint author), Los Alamos Natl Lab, Div Theoret, Fluid Dyn Grp, Mail Stop B216, Los Alamos, NM 87545 USA. NR 15 TC 5 Z9 5 U1 1 U2 1 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 0733-9399 EI 1943-7889 J9 J ENG MECH JI J. Eng. Mech. PD APR PY 1998 VL 124 IS 4 BP 377 EP 384 DI 10.1061/(ASCE)0733-9399(1998)124:4(377) PG 8 WC Engineering, Mechanical SC Engineering GA ZC823 UT WOS:000072621700003 ER PT J AU Bogen, KT Keating, GA Meissner, S Vogel, JS AF Bogen, KT Keating, GA Meissner, S Vogel, JS TI Initial uptake kinetics in human skin exposed to dilute aqueous trichloroethylene in vitro SO JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY LA English DT Article DE chlorinated solvents; percutaneous; permeability; volatile organic compounds; water ID ESTIMATING DERMAL ABSORPTION; ORGANIC-CHEMICALS; STRATUM-CORNEUM; WATER; PERMEABILITY; CHLOROFORM; MODEL; TETRACHLOROETHYLENE; PHARMACOKINETICS; RAT AB In vitro uptake of C-14-labeled trichloroethylene (TCE) from dilute (similar to 5-ppb) aqueous solutions into human surgical skirt was measured using accelerator mass spectrometry (AMS). We analyzed 105 breast-tissue samples obtained from three subjects, representing 27 separate exposure experiments conducted at similar to 20 degrees C for 0, 1, 5, 15, 30, or 60 min. The AMS data obtained positively correlate with (p approximate to 0) and vary significantly nonlinearly with (p = 0.0094) exposure duration. These data are inconsistent (p approximate to 0) with predictions made for TCE by a proposed U.S. Environmental Protection Agency (USEPA) dermal exposure model, even when uncertainties in its recommended parameter values for TCE are consider-ed, but are consistent (p = 0.17) with a I-compartment model for exposed skin-surface tissue governed in vitro by a maximum effective permeability of K-p* = 0.28 cm h(-1) (+/-7.0%) and a first-order rate constant of k(l) = 1.2 h(-1) (+/-16%). The apparent compartment depth is estimated to be approximately 40-100 mu m, i.e., to comprise much or all of the epidermis. In contrast, the USEPA model implies only negligible TCE penetration beyond SC during a I-h exposure. The Kd estimate based on the 1-compartment model fit is consistent with estimates for TCE based on in vivo studies, which supports the hypothesis that the USEPA model underpredicts short-term dermal uptake of TCE from water It is shown that for humans, this fit also implies that normalized total uptake of TCE from wafer by short-term dermal contact in vivo is predicted to be fK(p)*, where f is similar to 80% for longer normothermic exposures and similar to 95% during a brief hot shower or bath. This study illustrates the power of AMS to facilitate analyses of contaminant biodistribution and uptake kinetics at very low environmental concentrations. C1 Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, Livermore, CA 94550 USA. RP Bogen, KT (reprint author), Univ Calif Lawrence Livermore Natl Lab, Hlth & Ecol Assessment Div, L-396,7000 E Ave, Livermore, CA 94550 USA. NR 40 TC 15 Z9 15 U1 1 U2 3 PU PRINCETON SCIENTIFIC PUBL INC PI PRINCETON PA PO BOX 2155, PRINCETON, NJ 08543 USA SN 1053-4245 J9 J EXPO ANAL ENV EPID JI J. Expo. Anal. Environ. Epidemiol. PD APR-JUN PY 1998 VL 8 IS 2 BP 253 EP 271 PG 19 WC Environmental Sciences; Public, Environmental & Occupational Health; Toxicology SC Environmental Sciences & Ecology; Public, Environmental & Occupational Health; Toxicology GA ZK371 UT WOS:000073313700011 PM 9577754 ER PT J AU Luhmann, JG Gosling, JT Hoeksema, JT Zhao, X AF Luhmann, JG Gosling, JT Hoeksema, JT Zhao, X TI The relationship between large-scale solar magnetic field evolution and coronal mass ejections SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID HELIOSPHERIC CURRENT SHEET; SMM OBSERVATIONS; FLUX; WIND; EVENTS; CYCLE; INTERPLANETARY; STREAMER AB The idea that coronal mass ejections (CMEs) originate from the evolution of the large-scale solar field and in particular arise from regions of freshly opening coronal flux is reexamined using a new approach, Potential field models constructed from Wilcox Solar Observatory magnetograms are applied to study both the rate of "opening" of coronal fields with time and the locations of observed CMEs compared to the inferred newly open field regions on the Sun, Case studies are drawn from SMM coronagraph data, Yohkoh soft X ray images, and counterstreaming electron events observed on the ICE spacecraft, The results suggest that the large-scale field evolution paradigm of CMEs deserves further attention and has potential for applications to "space weather" forecasting. C1 Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. Stanford Univ, Ctr Space Sci & Astrophys, Stanford, CA 94305 USA. RP Luhmann, JG (reprint author), Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. NR 36 TC 54 Z9 54 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 1998 VL 103 IS A4 BP 6585 EP 6593 DI 10.1029/97JA03727 PG 9 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZF972 UT WOS:000072951700010 ER PT J AU Sibeck, DG Takahashi, K Yumoto, K Reeves, GD AF Sibeck, DG Takahashi, K Yumoto, K Reeves, GD TI Concerning the origin of signatures in dayside equatorial ground magnetograms SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID PLANETARY MAGNETIC-FIELD; ELECTRIC-FIELDS; DISTURBED CONDITIONS; FLUX EROSION; MAGNETOSPHERE; IONOSPHERE; SUBSTORM AB Previous reports suggest that north/south interplanetary magnetic field (IMF) turnings are the predominant cause of north/south fluctuations in dayside equatorial ground magnetograms. We compare 210 degrees Magnetic Meridian (MM) ground magnetograms with simultaneous IMP 8 solar wind and LANL geosynchronous energetic electron observations during 1993 and 1994 to search for this effect. About one third of the northward equatorial magnetic field enhancements can be associated with increases in the solar wind dynamic pressure, a second third with substorm onset as measured by energetic electron injections, and the final third with southward IMF turnings, An alternative explanation can be found for most enhancements associated with north/south IMF variations but not for enhancements associated with solar wind dynamic pressure variations or substorm onsets. Our results suggest that dayside equatorial ground magnetograms may be used to monitor both solar wind dynamic pressure variations and nightside substorm onsets. C1 Johns Hopkins Univ, Appl Phys Lab, Laurel, MD 20723 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Solar Terr Environm Lab, Toyokawa, Japan. Kyushu Univ, Dept Earth & Planetary Sci, Fukuoka 812, Japan. RP Sibeck, DG (reprint author), Johns Hopkins Univ, Appl Phys Lab, Johns Hopkins Rd, Laurel, MD 20723 USA. RI Sibeck, David/D-4424-2012; Reeves, Geoffrey/E-8101-2011 OI Reeves, Geoffrey/0000-0002-7985-8098 NR 31 TC 9 Z9 9 U1 0 U2 0 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 1998 VL 103 IS A4 BP 6763 EP 6769 DI 10.1029/97JA03600 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZF972 UT WOS:000072951700025 ER PT J AU Birn, J Hesse, M Schindler, K AF Birn, J Hesse, M Schindler, K TI Formation of thin current sheets in space plasmas SO JOURNAL OF GEOPHYSICAL RESEARCH-SPACE PHYSICS LA English DT Article ID NEAR-EARTH MAGNETOTAIL; GROWTH-PHASE; TAIL; CONVECTION; SUBSTORMS; CONFIGURATIONS; FIELDS AB The formation of thin current sheets is investigated on the basis of an adiabatic ideal MHD model. The primary applications are the substorm growth phase in Earth's magnetotail, prior to the dynamic expansion phase, and evolving structures in the solar corona which may similarly lead into an eruption such as a disappearing filament or a flare. A time-dependent MHD code is used to study the evolution under the influence of an external electric field applied at the boundaries of the system. This electric field may be considered as the consequence of the coupling with the solar wind in Earth's case or as a representation of a converging footpoint motion in a bipolar region on the solar photosphere. Thin current sheets are found to form both in the high-beta and low-beta case (where beta is the ratio of plasma pressure over magnetic pressure). They form in the closed field region even though the external electric field and the footpoint displacement are applied predominantly in the surrounding open field region. Within the limits of numerically stable solutions, the current sheet thickness and the maximum current density remain finite, scaling with a high power of the lobe field increase. Larger amplitudes of the current density and a stronger localization of the current sheet in the radial direction are found when the applied electric field decays more rapidly away from Earth or the solar surface. The value of gamma, the polytropic index, has little influence on the evolution and the final current sheet structure. Force-free configurations behave similarly as their equivalent high-beta current sheets. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. NASA, Goddard Space Flight Ctr, Electrodynam Branch, Greenbelt, MD 20771 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. RP Birn, J (reprint author), Univ Calif Los Alamos Natl Lab, MS D466, Los Alamos, NM 87545 USA. RI Hesse, Michael/D-2031-2012 NR 25 TC 37 Z9 38 U1 1 U2 3 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA J9 J GEOPHYS RES-SPACE JI J. Geophys. Res-Space Phys. PD APR 1 PY 1998 VL 103 IS A4 BP 6843 EP 6852 DI 10.1029/97JA03602 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZF972 UT WOS:000072951700031 ER PT J AU Rice, SF Steeper, RR AF Rice, SF Steeper, RR TI Oxidation rates of common organic compounds in supercritical water SO JOURNAL OF HAZARDOUS MATERIALS LA English DT Article DE oxidation; kinetics; supercritical water; waste treatment; high pressure ID RAMAN-SPECTROSCOPIC MEASUREMENT; ACETIC-ACID OXIDATION; METHANOL OXIDATION; KINETICS; CONVERSION AB Supercritical water oxidation is a rapidly emerging thermal waste-processing technology with potential as a hazardous-waste-treatment method for a variety of industrial chemicals ranging from common organic solvents to complex industrial formulations, An important design consideration in the development of supercritical water oxidation is the optimization of reactor operating temperature and feed preheat temperatures. In this paper, the temperature dependence of the oxidation in supercritical water of seven common organic compounds is examined over a temperature range of 430-585 degrees C and reaction times ranging from 7 to 30 s at 27.6 MPa (4000 psi). The reactants are examined at approximate concentrations of 0.4 wt.% at conversion efficiencies from 50% to > 99.9%, The materials examined were methanol, phenol, methyl ethyl ketone, ethylene glycol, acetic acid, methylene chloride, and 1,1,1-trichloroethane. The conversion of these compounds was monitored using total organic carbon and gas chromatography on liquid effluent samples. The results indicate that for most compounds, temperatures over 550 degrees C and residence times near 20 s afford conversion efficiencies of greater than 99.95% based on total organic carbon. (C) 1998 Elsevier Science B.V. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. RP Rice, SF (reprint author), Sandia Natl Labs, Combust Res Facil, POB 969, Livermore, CA 94551 USA. NR 20 TC 62 Z9 66 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3894 J9 J HAZARD MATER JI J. Hazard. Mater. PD APR PY 1998 VL 59 IS 2-3 BP 261 EP 278 DI 10.1016/S0304-3894(97)00152-0 PG 18 WC Engineering, Environmental; Engineering, Civil; Environmental Sciences SC Engineering; Environmental Sciences & Ecology GA ZN380 UT WOS:000073640100012 ER PT J AU Burges, SJ Wigmosta, MS Meena, JM AF Burges, Stephen J. Wigmosta, Mark S. Meena, Jack M. TI HYDROLOGICAL EFFECTS OF LAND-USE CHANGE IN A ZERO-ORDER CATCHMENT SO JOURNAL OF HYDROLOGIC ENGINEERING LA English DT Article AB Hydrologic modeling and relatively simple monitoring were used to estimate the hydrologic balance for two geographically close and, in the undisturbed state, hydrologically similar, zero-order basins: one undeveloped forest and the other suburban. Continuous precipitation and streamflow were measured in each basin; the model was used to estimate time series of evapotranspiration and ground-water recharge over a 40-yr period. The suburban catchment was denuded of forest cover, soil thickness was reduced, and 30% of the area was covered with impervious surfaces. The amount of annual precipitation that becomes runoff ranged from 12 to 30% in the forested catchment and 44 to 48% in the suburban catchment where runoff from pervious areas accounts for 40-60% of the annual total. The peak flow rate per unit area for an approximate 24-h, 50-yr rainfall was more than 10 times higher from the pervious area at the suburban site than at the forested site. These findings emphasize the need to consider surface flow from all sources in the catchment when considering mitigation measures. C1 [Burges, Stephen J.] Univ Washington, Dept Civil Engn, Seattle, WA 98195 USA. [Wigmosta, Mark S.] Pacific NW Natl Lab, Richland, WA 99352 USA. [Meena, Jack M.] States W Water Resour Corp, Cheyenne, WY 82001 USA. RP Burges, SJ (reprint author), Univ Washington, Dept Civil Engn, Seattle, WA 98195 USA. FU U.S. Geological Survey (USGS), Department of the Interior, under USGS [14-08-0001-G1887] FX The writers appreciate thoughtful discussions with colleagues Dennis Lettenmaier, Tom Dunne, and Terry Cundy. At various stages important help in the form of fieldwork, discussions, and overall contributions to our understanding was received from Andy Tuthill, Brian Williams, and Bryson Bates, respectively. The writers are indebted particularly to Jim Kramer, Manager, King County, Department of Public Works, Surface Water Management Division for his total backing of the project and the support he provided through his professional staff colleagues, Derek Booth, Joanna Richey, Bruce Barker, and Rhett Jackson; instrumentation experts Dave Funke, John Koon, and Tim Egan; and graphics expert Fred Bentler. The writers could not have undertaken the project without the essential help of the King County Surface Water Management Division. This research was supported by the U.S. Geological Survey (USGS), Department of the Interior, under USGS Award 14-08-0001-G1887. The views and conclusions contained in this document are those of the writers and should not be interpreted as necessarily representing the official policies, either expressed or implied, of the U.S. Government. NR 13 TC 48 Z9 50 U1 0 U2 15 PU ASCE-AMER SOC CIVIL ENGINEERS PI RESTON PA 1801 ALEXANDER BELL DR, RESTON, VA 20191-4400 USA SN 1084-0699 J9 J HYDROL ENG JI J. Hydrol. Eng. PD APR PY 1998 VL 3 IS 2 BP 86 EP 97 DI 10.1061/(ASCE)1084-0699(1998)3:2(86) PG 12 WC Engineering, Civil; Environmental Sciences; Water Resources SC Engineering; Environmental Sciences & Ecology; Water Resources GA V15AL UT WOS:000207774800002 ER PT J AU Xu, KL Goldstein, B Holowka, D Baird, B AF Xu, KL Goldstein, B Holowka, D Baird, B TI Kinetics of multivalent antigen DNP-BSA binding to IgE-Fc epsilon RI in relationship to the stimulated tyrosine phosphorylation of Fc epsilon RI SO JOURNAL OF IMMUNOLOGY LA English DT Article ID BASOPHILIC LEUKEMIA-CELLS; HIGH-AFFINITY RECEPTOR; CROSS-LINKING; SIGNAL-TRANSDUCTION; BIVALENT LIGAND; SURFACE; COMPLEXES; DISSOCIATION; AGGREGATION AB Multivalent DNP-BSA is commonly used to cross-link anti-DNP IgE bound to Fc epsilon RI to stimulate cellular responses, although key features of the binding process are unknown. Fluorescence quenching can be used to study the kinetics of DNP-BSA binding to FITC-IgE. We observe that DNP-BSA binds more slowly to IgE than does an equimolar amount of a monovalent DNP ligand, suggesting that the average effective number of DNP groups per BSA is less than one, The binding data are well described by a transient hapten exposure model in which most of the DNP groups are unavailable for binding but have some probability of becoming exposed and available for binding during the time of the binding measurement. Additional experiments indicate that, for suboptimal to optimal concentrations of DNP-BSA, most of the FITC fluorescence quenching on the cell surface is due to cross-linking events. With these concentrations at 15 degrees C, the kinetics of FITC fluorescence quenching by DNP-BSA correlates with the kinetics of DNP-BSA-stimulated tyrosine phosphorylation of Fc epsilon RI. At 35 degrees C, the phosphorylation kinetics are biphasic during the time period in which cross-linking continues to increase, Our results establish a quantitative relationship between the timecourse for cross-linking by multivalent Ag and Fc epsilon RI-mediated signaling, and they provide the means to predict the kinetics of cross-linking under a wide variety of conditions. C1 Cornell Univ, Baker Lab, Dept Chem, Ithaca, NY 14853 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. RP Holowka, D (reprint author), Cornell Univ, Baker Lab, Dept Chem, Ithaca, NY 14853 USA. FU NIAID NIH HHS [AI22449]; NIGMS NIH HHS [GM35556] NR 37 TC 30 Z9 30 U1 0 U2 5 PU AMER ASSOC IMMUNOLOGISTS PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0022-1767 J9 J IMMUNOL JI J. Immunol. PD APR 1 PY 1998 VL 160 IS 7 BP 3225 EP 3235 PG 11 WC Immunology SC Immunology GA ZD573 UT WOS:000072700100019 PM 9531278 ER PT J AU Stilianakis, NI Perelson, AS Hayden, FG AF Stilianakis, NI Perelson, AS Hayden, FG TI Emergence of drug resistance during an influenza epidemic: Insights from a mathematical model SO JOURNAL OF INFECTIOUS DISEASES LA English DT Article ID A VIRUS; NURSING-HOME; AMANTADINE; RIMANTADINE; PROPHYLAXIS; INFECTION; TRANSMISSION; POPULATIONS; TRIAL; H3N2 AB A model was developed for the emergence of drug-resistant influenza viruses during a closed population influenza epidemic that occurs in a single wave. The model was used to consider several treatment and chemoprophylaxis strategies and to determine their effects on the spread of the infection. The model predicts frequent emergence and transmission of drug-resistant viruses with certain treatment scenarios. According to the model, chemoprophylaxis of susceptible persons (without treatment of those who are symptomatic) may be the best way to reduce the force of an epidemic and to keep development of drug resistance low. The model predictions indicate that the relative transmissibility of resistant variants compared with wild type virus and the choice of the treatment or chemoprophylaxis strategy can be decisive for the spread of drug-resistant viruses, a feature that may be crucial in a pandemic. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM USA. Univ Virginia, Sch Med, Dept Internal Med, Charlottesville, VA 22908 USA. Univ Virginia, Sch Med, Dept Pathol, Charlottesville, VA 22908 USA. RP Hayden, FG (reprint author), Univ Virginia, Hlth Sci Ctr, Dept Internal Med, Box 473, Charlottesville, VA 22908 USA. NR 32 TC 76 Z9 80 U1 0 U2 4 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0022-1899 J9 J INFECT DIS JI J. Infect. Dis. PD APR PY 1998 VL 177 IS 4 BP 863 EP 873 PG 11 WC Immunology; Infectious Diseases; Microbiology SC Immunology; Infectious Diseases; Microbiology GA ZD747 UT WOS:000072719400005 PM 9534957 ER PT J AU Elias, PM Nau, P Hanley, K Cullander, C Crumrine, D Bench, G Sideras-Haddad, E Mauro, T Williams, ML Feingold, KR AF Elias, PM Nau, P Hanley, K Cullander, C Crumrine, D Bench, G Sideras-Haddad, E Mauro, T Williams, ML Feingold, KR TI Formation of the epidermal calcium gradient coincides with key milestones of barrier ontogenesis in the rodent SO JOURNAL OF INVESTIGATIVE DERMATOLOGY LA English DT Article DE epidermis; permeability barrier; protein induced X-ray emission (PIXE); transepidermal water loss ID ULTRASTRUCTURAL-LOCALIZATION; PERMEABILITY BARRIER; MURINE EPIDERMIS; STRATUM-CORNEUM; LIPID-SYNTHESIS; WATER-LOSS; DIFFERENTIATION; EXPRESSION; DISRUPTION; RECOVERY AB The epidermal permeability barrier forms late in gestation, coincident with decreased lipid synthesis, increased lipid processing, and development of a mature, multilayered stratum corneum. Prior studies have shown that changes in the epidermal Ca++ gradient in vivo regulate lamellar body secretion and lipid synthesis, and modulations in extracellular Ca++ in vitro also regulate keratinocyte differentiation. We asked here whether a Ca++ gradient forms in fetal epidermis in utero, and whether its emergence correlates with key developmental milestones of barrier formation and stratum corneum development. Using either ion precipitation or proton induced X-ray emission analysis of fetal mouse and rat skin, we showed that a Ca++ gradient is not present at gestational days 16-18, prior to barrier formation, and that a gradient forms coincident with the emergence of barrier competence (day 19, mouse; day 20, rat) prior to birth, These results are consistent with a role for Ca++ in the regulation of key metabolic events leading to barrier formation. Whether the calcium gradient is formed actively or passively remains to be determined. C1 Vet Adm Med Ctr, Dermatol Serv 190, San Francisco, CA 94121 USA. Vet Adm Med Ctr, Med Metab Serv, San Francisco, CA 94121 USA. Univ Calif San Francisco, Sch Med, Dept Dermatol, San Francisco, CA 94143 USA. Univ Calif San Francisco, Sch Med, Dept Med, San Francisco, CA 94143 USA. Univ Calif San Francisco, Sch Med, Dept Biopharmaceut Sci, San Francisco, CA 94143 USA. Univ Calif San Francisco, Sch Med, Dept Pharmaceut Sci, San Francisco, CA 94143 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. RP Elias, PM (reprint author), Vet Adm Med Ctr, Dermatol Serv 190, 4150 Clement St, San Francisco, CA 94121 USA. FU NIAMS NIH HHS [AR19098, AR39369, AR39448] NR 27 TC 61 Z9 61 U1 2 U2 6 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0022-202X J9 J INVEST DERMATOL JI J. Invest. Dermatol. PD APR PY 1998 VL 110 IS 4 BP 399 EP 404 DI 10.1046/j.1523-1747.1998.00151.x PG 6 WC Dermatology SC Dermatology GA ZD914 UT WOS:000072738200017 PM 9540982 ER PT J AU Yarosh, D Klein, J O'Connor, A Kibitel, J Brash, D Hejmadi, V Sutherland, B AF Yarosh, D Klein, J O'Connor, A Kibitel, J Brash, D Hejmadi, V Sutherland, B TI Tumor necrosis factor-alpha gene expression is induced by cyclobutyl pyrimidine dimers in DNA. SO JOURNAL OF INVESTIGATIVE DERMATOLOGY LA English DT Meeting Abstract C1 Appl Genet Inc, Freeport, NY USA. Yale Univ, New Haven, CT 06520 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU BLACKWELL SCIENCE INC PI MALDEN PA 350 MAIN ST, MALDEN, MA 02148 USA SN 0022-202X J9 J INVEST DERMATOL JI J. Invest. Dermatol. PD APR PY 1998 VL 110 IS 4 BP 648 EP 648 PG 1 WC Dermatology SC Dermatology GA ZD914 UT WOS:000072738201084 ER PT J AU Essien, M Keicher, DM AF Essien, M Keicher, DM TI Enhanced imaging of a pulsed Nd : YAG metal vapor plume SO JOURNAL OF LASER APPLICATIONS LA English DT Article DE laser welding; laser plume; high-speed schlieren imaging ID ELECTRON-BEAM; LASER; PENETRATION; PLASMA; MODEL AB Understanding the physical processes that occur in laser material processing is necessary for developing computational models that simulate the laser/material interaction, acid for real-time process monitoring and control. This work was performed to gain an increased understanding of the dynamics of the vapor ejected from a metal surface during the laser welding process. The plume is imaged using a laser schlieren technique that detects the refraction of a probe beam. A computer-generated, graded filter replaces the traditional knife-edge schlieren filter, and yields images with enhanced resolution and sensitivity. Images show that intense vaporization begins within the first 10 mu s after the laser pulse is incident on the metal surface, and that the vapor propagates as two distinct waves. The first wave is a spherical wave, and is initiated just after the beginning of the laser pulse. For typical laser welding surface intensities, the second, mon energetic wave, is initiated approximately 0.6 to 1.5 ms after the beginning of the laser pulse, and propagates away from the surface in a focused trajectory. The results suggest that a simple optical method of detecting the production of a keyhole weld may be performed using laser schlieren imaging. (C) 1998 Laser Institute of America. [S1042-346X(98)00502-6]. C1 Sandia Natl Labs, Org 1833, Albuquerque, NM 87185 USA. Optomec Design Co, Albuquerque, NM 87107 USA. RP Essien, M (reprint author), Sandia Natl Labs, Org 1833, POB 5800, Albuquerque, NM 87185 USA. NR 19 TC 2 Z9 2 U1 2 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1042-346X J9 J LASER APPL JI J. Laser Appl. PD APR PY 1998 VL 10 IS 2 BP 85 EP 89 PG 5 WC Materials Science, Multidisciplinary; Optics; Physics, Applied SC Materials Science; Optics; Physics GA ZG147 UT WOS:000072970800006 ER PT J AU Reijerse, EJ Tyryshkin, AM Dikanov, SA AF Reijerse, EJ Tyryshkin, AM Dikanov, SA TI Complete determination of nitrogen quadrupole and hyperfine tensors in an oxovanadium complex by simultaneous fitting of multifrequency ESEEM powder spectra SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID ELECTRON-SPIN-ECHO; HISTIDINE HYDROCHLORIDE MONOHYDRATE; ENVELOPE-MODULATION; SINGLE-CRYSTALS; 2-DIMENSIONAL ESEEM; DISORDERED SOLIDS; SPECTROSCOPY; HYSCORE; LIGAND; VO2+ AB One-dimensional C-and X-band as well as two-dimensional X-band ESEEM experiments were performed on the complex oxobis( 2-methylquinolin-8-olato) vanadium(IV) in fro ten solution. A N-14 ESEEM simulation strategy based on initial first-and second-order perturbation analysis of peak positions in orientationally selected ESEEM spectra is presented. The constraint parameters extracted enable one to reduce the number of free fitting parameters for each nitrogen from 10 to 4, These are the alpha, beta resp. the phi, theta Euler angles of the NQI and the HFI tensor defined in the coordinate system of the axial g tenser. The local symmetry of the complex allows one to reduce the number of free parameters to two angles only. Subsequently, a grid search in the remaining Euler space produced the starting parameters for the final fit of the N-14 hyperfine and quadrupole tensors. The anisotropic nitrogen hyperfine interaction tensor was found to be strongly nonaxial (0.06, 0.51, -0.57) MHz with the components significantly smaller than the isotropic hyperfine constant -6.18 MHz, In contrast, the quadrupole tensor with K = 0.58 MHz is close to axial (eta = 0.13), These tensors share the principal axis normal to the ligand plane las imposed by the local symmetry). The axes in the ligand plane are, however, rotated 50 degrees with respect to each other. The orientation of the quadrupole tensor axes correlate within 10 degrees with the orientation of the ligand plane following from the X-ray structure. (C) 1998 Academic Press. C1 Univ Nijmegen, Dept Mol Spect, NL-6525 ED Nijmegen, Netherlands. Russian Acad Sci, Inst Chem Kinet & Combust, Novosibirsk 630090, Russia. Pacific NW Lab, Richland, WA 99352 USA. RP Univ Nijmegen, Dept Mol Spect, Toernooiveld, NL-6525 ED Nijmegen, Netherlands. RI Tyryshkin, Alexei/A-5219-2008 NR 34 TC 15 Z9 15 U1 2 U2 7 PU ACADEMIC PRESS INC ELSEVIER SCIENCE PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 EI 1096-0856 J9 J MAGN RESON JI J. Magn. Reson. PD APR PY 1998 VL 131 IS 2 BP 295 EP 309 DI 10.1006/jmre.1997.1339 PG 15 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA ZL914 UT WOS:000073486200016 ER PT J AU Gregory, DM Gerald, RE Botto, RE AF Gregory, DM Gerald, RE Botto, RE TI Pore-structure determinations of silica aerogels by Xe-129 NMR spectroscopy and imaging SO JOURNAL OF MAGNETIC RESONANCE LA English DT Article ID MICROPOROUS SOLIDS; ZEOLITES AB Silica aerogels represent a new class of open-pore materials with pore dimensions on a scale of tens of nanometers, and are thus classified as mesoporous materials. In this work, we show that the combination of NMR spectroscopy and chemical-shift selective magnetic resonance imaging (MRI) can resolve some of the important aspects of the structure of silica aerogels. The use of xenon as a gaseous probe in combination with spatially resolved NMR techniques is demonstrated to be a powerful, new approach for characterizing the average pore structure and steady-state spatial distributions of xenon atoms in different physicochemical environments. Furthermore, dynamic NMR magnetization transfer experiments and pulsed-field gradient (PFG) measurements have been used to characterize exchange processes and diffusive motion of xenon in samples at equilibrium. In particular, this new NMR approach offers unique information and insights into the nanoscopic pore structure and microscopic morphology of aerogels and the dynamical behavior of occluded adsorbates. MRI provides spatially resolved information on the nature of the flaw regions found in these materials. Pseudo-first-order rate constants for magnetization transfer among the bulk and occluded xenon phases indicate xenon-exchange rate constants on the order of 1 s(-1) for specimens having volumes of 0.03 cm(3). PFG diffusion measurements show evidence of anisotropic diffusion for xenon occluded within aerogels, with nominal self-diffusivity coefficients on the order of D = 10(-3) cm(2)/s. (C) 1998 Academic Press. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Botto, RE (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 30 TC 25 Z9 25 U1 0 U2 4 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 1090-7807 J9 J MAGN RESON JI J. Magn. Reson. PD APR PY 1998 VL 131 IS 2 BP 327 EP 335 DI 10.1006/jmre.1998.1358 PG 9 WC Biochemical Research Methods; Physics, Atomic, Molecular & Chemical; Spectroscopy SC Biochemistry & Molecular Biology; Physics; Spectroscopy GA ZL914 UT WOS:000073486200019 ER PT J AU Ehrenberg, H Wltschek, G Rodriguez-Carvajal, J Vogt, T AF Ehrenberg, H Wltschek, G Rodriguez-Carvajal, J Vogt, T TI Magnetic structures of the tri-rutiles NiTa2O6 and NiSb2O6 SO JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS LA English DT Article DE magnetic structure; magnetic ordering; neutron diffraction ID COTA2O6 AB The magnetic structures of the tri-rutiles NiSb2O6 and NiTa2O6 were determined by neutron powder diffraction. In both cases the magnetic moments are collinear aligned parallel to [110]. In the tetragonal plane ferromagnetic and antiferromagnetic chains exist, which are perpendicular to each other. But in antimonate these chains run along the [100]- and [010]-directions in contrast to [110] and [1(1) over bar0$] for the tantalate. Along the [001]-direction the orientations are alternating for both compounds. k(z) = 1/2. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Tech Univ Darmstadt, Fachbereich Mat Wissensch, Fachgebiet Strukturforsch, D-64287 Darmstadt, Germany. Ctr Etud Saclay, Lab Leon Brillouin, F-91191 Gif Sur Yvette, France. Assoc Univ Inc, Brookhaven Natl Lab, Upton, NY 11973 USA. RP Ehrenberg, H (reprint author), Tech Univ Darmstadt, Fachbereich Mat Wissensch, Fachgebiet Strukturforsch, Petersenstr 30, D-64287 Darmstadt, Germany. RI Rodriguez-Carvajal, Juan/C-4362-2008; Vogt, Thomas /A-1562-2011; Ehrenberg, Helmut/M-7090-2013 OI Rodriguez-Carvajal, Juan/0000-0001-5582-2632; Vogt, Thomas /0000-0002-4731-2787; Ehrenberg, Helmut/0000-0002-5134-7130 NR 8 TC 14 Z9 14 U1 2 U2 35 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-8853 J9 J MAGN MAGN MATER JI J. Magn. Magn. Mater. PD APR PY 1998 VL 184 IS 1 BP 111 EP 115 DI 10.1016/S0304-8853(97)01122-0 PG 5 WC Materials Science, Multidisciplinary; Physics, Condensed Matter SC Materials Science; Physics GA ZH109 UT WOS:000073073100015 ER PT J AU Barcellos-Hoff, MH AF Barcellos-Hoff, MH TI The potential influence of radiation-induced microenvironments in neoplastic progression SO JOURNAL OF MAMMARY GLAND BIOLOGY AND NEOPLASIA LA English DT Article DE extracellular matrix; transforming growth factor-beta; carcinogenesis; stromal/epithelial interactions; ionizing radiation ID GROWTH-FACTOR-BETA; HUMAN-BREAST-CANCER; MISMATCH REPAIR DEFICIENCY; CELL MATRIX INTERACTIONS; INDUCED LUNG INJURY; MAMMARY-GLAND; TGF-BETA; TRANSFORMING GROWTH-FACTOR-BETA-1; EXTRACELLULAR-MATRIX; PLASMINOGEN-ACTIVATOR AB Ionizing radiation is a complete carcinogen, able both to initiate and promote neoplastic progression and is a known carcinogen of human and murine mammary gland. Tissue response to radiation is a composite of genetic damage, cell death and induction of new gene expression patterns. Although DNA damage is believed to initiate carcinogenesis, the contribution of these other aspects of radiation response are beginning to be explored. Our studies demonstrate that radiation elicits rapid and persistent global alterations in the mammary gland microenvironment. We postulate that radiation-induced microenvironments may affect epithelial cells neoplastic transformation by altering their number or susceptibility. Alternatively, radiation induced microenvironments may exert a selective force on initiated cells and/or be conducive to progression. A key impetus for these studies is the possibility that blocking these events could be a strategy to interrupt neoplastic progression. C1 Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Barcellos-Hoff, MH (reprint author), Lawrence Berkeley Natl Lab, Div Life Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. EM mhbarcellos-hoff@lbl.gov FU NCI NIH HHS [CA-51841] NR 75 TC 50 Z9 51 U1 0 U2 0 PU SPRINGER/PLENUM PUBLISHERS PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1083-3021 J9 J MAMMARY GLAND BIOL JI J. Mammary Gland Biol. Neoplasia PD APR PY 1998 VL 3 IS 2 BP 165 EP 175 DI 10.1023/A:1018794806635 PG 11 WC Oncology; Endocrinology & Metabolism; Physiology SC Oncology; Endocrinology & Metabolism; Physiology GA 115VH UT WOS:000075686300006 PM 10819525 ER PT J AU Schmeichel, KL Weaver, VM Bissell, MJ AF Schmeichel, KL Weaver, VM Bissell, MJ TI Structural cues from the tissue microenvironment are essential determinants of the human mammary epithelial cell phenotype SO JOURNAL OF MAMMARY GLAND BIOLOGY AND NEOPLASIA LA English DT Article DE microenvironment; human breast cancer; extracellular matrix; mammary gland; tumorigenesis ID RECONSTITUTED BASEMENT-MEMBRANE; CLONAL CHROMOSOME-ABNORMALITIES; GROWTH-FACTOR REQUIREMENTS; BREAST-CANCER PROGRESSION; CAPILLARY-LIKE STRUCTURES; HUMAN-ENDOTHELIAL CELLS; EXTRACELLULAR-MATRIX; GENE-EXPRESSION; IN-VITRO; 3-DIMENSIONAL CULTURE AB Historically, the study of normal human breast function and breast disorders has been significantly impaired by limitations inherent to available model systems. Recent improvements in human breast epithelial cell lines and three-dimensional (3-D)(3) culture systems have contributed to the development of in vitro model systems that recapitulate differentiated epithelial cell phenotypes with remarkable fidelity. Molecular characterization of these human breast cell models has demonstrated that normal breast epithelial cell behavior is determined in part by the precise interplay that exists between a cell and its surrounding microenvironment. Recent functional studies of integrins in a human model system provide evidence to support the idea that the structural stability afforded by integrin-mediated cell-extracellular matrix interactions is an important determinant of normal cellular behavior, and that alterations in tissue structure can give rise to tumorigenic progression. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Life Sci, Berkeley, CA 94720 USA. FU NCI NIH HHS [CA57621, CA64786, R01 CA057621, R01 CA057621-07, R01 CA064786, R01 CA064786-05, R37 CA064786] NR 93 TC 62 Z9 63 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1083-3021 J9 J MAMMARY GLAND BIOL JI J. Mammary Gland Biol. Neoplasia PD APR PY 1998 VL 3 IS 2 BP 201 EP 213 DI 10.1023/A:1018751124382 PG 13 WC Oncology; Endocrinology & Metabolism; Physiology SC Oncology; Endocrinology & Metabolism; Physiology GA 115VH UT WOS:000075686300009 PM 10819528 ER PT J AU Jensen, TR Norby, P Hanson, JC Simonsen, O Skou, EM Stein, PC Boye, HA AF Jensen, TR Norby, P Hanson, JC Simonsen, O Skou, EM Stein, PC Boye, HA TI Hydrothermal synthesis and crystal structure of alpha-LiZnAsO4 SO JOURNAL OF MATERIALS CHEMISTRY LA English DT Article ID LITHIUM ZINC PHOSPHATE; RAY-POWDER DIFFRACTION; CHEMICAL-REACTIONS; STABILITY AB Single crystals of lithium zinc arsenate, alpha-LiZnAsO4, suitable for structure determination were prepared from an aqueous solution of H3AsO4, Zn(NO3)(2) and LiOH under hydrothermal conditions, at 240 degrees C. alpha-LiZnAsO4, has a fully ordered phenacite structure built from a three-dimensional framework of cornersharing AsO4, ZnO4 and LiO4 tetrahedra. The tetrahedra form nets of six-rings surrounded by six four-rings in the direction of the c-axis. alpha-LiZnAsO4 crystallises in the trigonal space group R3 (no. 146), a = 14.009(2), c = 9.386(2) Angstrom, Z = 18 and D-c = 3.958 g cm(-3). The structure was refined to: wR(F-2) = 0.130, R(F) = 0.050 and S = 0.982, for F-2 > 2 sigma(F-2). Synchrotron radiation, lambda = 0.9540 Angstrom, was used for single crystal diffraction giving 917 unique reflections. Solid state Li-7 MAS NMR showed a broadened Li signal implying more than one inequivalent Li (delta 0.21, reference: 1.00 mol dm(-3) LiCl). Linear thermal expansion coefficients in the temperature range 25-800 degrees C were determined using time resolved in situ synchrotron X-ray powder diffraction. A weak reversible, possibly second order, thermal event was observed at 682(1)degrees C using differential scanning calorimetry. C1 Odense Univ, Dept Chem, DK-5230 Odense M, Denmark. SUNY Stony Brook, Dept Chem, Stony Brook, NY 11794 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Odense Univ, Dept Anat & Cytol, DK-5230 Odense M, Denmark. RP Jensen, TR (reprint author), Odense Univ, Dept Chem, Campusvej 55, DK-5230 Odense M, Denmark. RI Hanson, jonathan/E-3517-2010; Stein, Paul/M-9044-2015; Norby, Poul/B-9047-2014; OI Stein, Paul/0000-0002-7723-1419; Norby, Poul/0000-0002-2590-7050; Jensen, Torben Rene/0000-0002-4278-3221 NR 48 TC 9 Z9 9 U1 0 U2 2 PU ROYAL SOC CHEMISTRY PI CAMBRIDGE PA THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON ROAD, CAMBRIDGE CB4 4WF, CAMBS, ENGLAND SN 0959-9428 J9 J MATER CHEM JI J. Mater. Chem. PD APR PY 1998 VL 8 IS 4 BP 969 EP 975 DI 10.1039/a707130b PG 7 WC Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZH105 UT WOS:000073072600025 ER PT J AU Broussard, PR Wall, MA Talvacchio, J AF Broussard, PR Wall, MA Talvacchio, J TI Structural characterization of YBa2Cu3O7-delta/Y2O3 composite films SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID MGO; Y2O3 AB Using 4-circle x-ray diffraction and transmission electron microscopy, we have studied the microstructure and in-plane orientation of the phases present in thin film composite mixtures of YBa2Cu3O7-delta and Y2O3. We see a high degree of in-plane orientation and have verified a previous prediction for the in-plane order of Y2BaCuO5 on (110) MgO. Transmission electron microscopy shows the composite films to be a mixture of two phases, with YBCO grain sizes of approximate to 1 mu m. We have also compared our observations of the in-plane order to the predictions of a modified near coincidence site lattice model. C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Northrop Grumman Sci & Technol Ctr, Pittsburgh, PA 15235 USA. RP Broussard, PR (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 7 TC 3 Z9 3 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD APR PY 1998 VL 13 IS 4 BP 954 EP 958 DI 10.1557/JMR.1998.0133 PG 5 WC Materials Science, Multidisciplinary SC Materials Science GA ZQ823 UT WOS:000073906500034 ER PT J AU Hirvonen, JP Torri, P Lappalainen, R Likonen, J Kung, H Jervis, JR Nastasi, M AF Hirvonen, JP Torri, P Lappalainen, R Likonen, J Kung, H Jervis, JR Nastasi, M TI Oxidation of MoSi2/SiC nanolayered composite SO JOURNAL OF MATERIALS RESEARCH LA English DT Article ID PRESSURE PLASMA DEPOSITION; LOW-TEMPERATURE OXIDATION; SIC-REINFORCED MOSI2; PEST AB The oxidation behavior of a nanolayered MoSi2/SiC composite material was determined at the temperature range of 400-900 degrees C in wet oxidation conditions. The samples were produced in the form of thin films using a sputtering technique from two different sources, and a rotating substrate holder, onto silicon single crystals and low carbon steel. For comparison, the oxidations of both constituents, MoSi2 and SiC, produced with the same sputtering technique, were measured separately. The microstructure of the MoSi2/SiC samples was determined with high resolution transmission electron microscopy (HRTEM), and the composition of the sputtered samples was measured using backscattering (BS) of protons. For quantitative determination of oxidation, the nuclear reaction O-16(d, p)O-17 was utilized. Oxide layers were also analyzed using a secondary ion mass spectrometry (SIMS) and the appearance of the oxidized surface with a scanning electron microscopy (SEM). As expected, the SiC films had both the lowest initial oxidation and steady state oxidation rate. The results show that the oxidation behavior of the MoSi2/SiC nanolayered composite material differs from that of both its constituents and involves a degradation mechanism of its own, resulting in the highest oxidation during the initial phase of the oxidation. A steady-state oxidation rate was observed after the initial transient phase to be the highest for the metastable C40 structure of the single MoSi2 layer. The oxidation rate of the nanolayered structure was retarded by the SiC layers. No signs of pest disintegration were observed on either of the MoSi2 containing coatings during the steady-state phase of the oxidation at 500 degrees C up to 40 h. Our results show that the oxidation of nanolayered structures can be only in part explained by the oxidation behavior of the constituents and that during the steady-state oxidation of the nanolayered structure the oxidation rate is largely determined by the constituent with the lowest oxidation rate and by the layered structure. C1 Inst Adv Mat, Joint Res Ctr, European Commiss, I-2120 Ispra, Italy. Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland. VTT Chem Technol, FIN-02044 VTT, Finland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hirvonen, JP (reprint author), Inst Adv Mat, Joint Res Ctr, European Commiss, I-2120 Ispra, Italy. NR 23 TC 8 Z9 8 U1 1 U2 4 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0884-2914 J9 J MATER RES JI J. Mater. Res. PD APR PY 1998 VL 13 IS 4 BP 965 EP 973 DI 10.1557/JMR.1998.0135 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA ZQ823 UT WOS:000073906500036 ER PT J AU Raman, SV AF Raman, SV TI Microstructures and leach rates of glass-ceramic nuclear waste forms developed by partial vitrification in a hot isostatic press SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID IMMOBILIZATION; ACTINIDES; SYNROC; ZIRCON AB A high level nuclear waste calcine simulant is transformed to a dense and durable glass-ceramic waste form by addition of glass and crystal forming components, and hot isostatic pressing at 1000 degrees C and 138 MPa. The waste forms are abundantly composed of zircon, beddeyelite, apatite, fluorite, greenockite and boroaluminosilicate glass. The crystal nucleating, glass forming and volatilizing components of the calcine are partitioned into crystalline and glass phases such that 95 wt% of the waste components, including actinide surrogates, stoichiometrically reside in the crystalline phases. This results in a high waste loading of 60-80 wt% calcine in the total glass-ceramic. The partitioning follows the natural association of elements, as a result, species like P avoid the glass phase. Instead glass accommodates the incompatible solutes like Cs. It minimizes porosity and bonds the polyphase ceramic microstructure, which resembles rhyolite or basalt volcanic rocks. Both glass and crystals contribute to high chemical durability, which is degraded when glass devitrifies with lowering of partial liquid viscosity by higher MgO additions. The devitrified phases are layered mica, dendritic nepheline and fibrous alkaline-earth borate. These phases are enriched in the mobile elements Cs, Na and B, respectively. (C) 1998 Chapman & Hall. C1 Lockheed Martin Idaho Technol, Idaho Natl Engn & Environm Lab, Dept Nucl Engn, Idaho Falls, ID 83402 USA. RP Raman, SV (reprint author), Lockheed Martin Idaho Technol, Idaho Natl Engn & Environm Lab, Dept Nucl Engn, Idaho Falls, ID 83402 USA. NR 28 TC 8 Z9 8 U1 3 U2 11 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD APR 1 PY 1998 VL 33 IS 7 BP 1887 EP 1895 DI 10.1023/A:1004313623562 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA ZD535 UT WOS:000072695900028 ER PT J AU Goldman, M Gronsky, R Pruitt, L AF Goldman, M Gronsky, R Pruitt, L TI The influence of sterilization technique and ageing on the structure and morphology of medical-grade ultrahigh molecular weight polyethylene SO JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE LA English DT Article ID RADIATION STERILIZATION; GAMMA-RADIATION; IRRADIATION AB The effects of four sterilization treatments (gamma radiation in nitrogen, electron-beam radiation, ethylene oxide gas, and no sterilization) on the structure and morphology of ultrahigh molecular weight polyethylene (UHMWPE) were monitored as a function of ageing time in air for a period of 1.5 y. Characterization techniques employed include differential scanning calorimetry, density gradient column, transmission electron microscopy, and small-angle X-ray scattering. Ethylene oxide gas does not affect the structure of the polymer. Both forms of radiation lead to measurable alterations of the material's structure, including an increase in crystallinity, an increase in density, and the enhancement of lamellae crystalline stacking. Most changes in structure occur in the first few months with little differences observed upon subsequent ageing in air. The sharpness of the crystalline-amorphous boundaries decreases with time for irradiated UHMWPE and is believed to be linked to the oxidation of the polymer. (C) 1998 Chapman & Hall. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Lawrence Berkeley Natl Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Mech Engn, Berkeley, CA 94720 USA. RP Goldman, M (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. NR 21 TC 24 Z9 24 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0957-4530 J9 J MATER SCI-MATER M JI J. Mater. Sci.-Mater. Med. PD APR PY 1998 VL 9 IS 4 BP 207 EP 212 DI 10.1023/A:1008836107186 PG 6 WC Engineering, Biomedical; Materials Science, Biomaterials SC Engineering; Materials Science GA ZA652 UT WOS:000072387500006 PM 15348894 ER PT J AU Moon, PJ Parulekar, SJ Tsai, SP AF Moon, PJ Parulekar, SJ Tsai, SP TI Competitive anion transport in desalting of mixtures of organic acids by batch electrodialysis SO JOURNAL OF MEMBRANE SCIENCE LA English DT Article DE competitive anion transport; desalting of multicomponent mixtures; electrodialysis; ion exchange membranes; liquid permeability and separations ID PERMSELECTIVE MEMBRANES; EXCHANGE MEMBRANE; SULFURIC-ACID; CITRIC-ACID; WASTE-WATER; SEPARATION; RECOVERY; FERMENTATION; IONS; CULTURE AB Desalting and separation of binary and quaternary acid mixtures via batch electrodialysis are investigated in this article. A monoselective cation exchange membrane and either a non-selective or a monoselective anion exchange membrane are employed in the electrodialysis stack. The effects of current density and composition of the initial feed of the electrodialysis stack (employing a non-selective anion exchange membrane) on its performance are studied in experiments involving mixtures of acetic and succinic acids. The effect of the type of the anion exchange membrane on the process performance is examined in desalting experiments involving a mixture of acetic, formic, lactic, and succinic acids, The trends observed in the experiments are interpreted in terms of species-specific parameters (such as molar concentration, charge on ionic species, molecular weight, degree of ionization, and ionic equivalent conductivity) and characteristics of anion exchange membrane used. (C) 1998 Elsevier Science B.V. C1 IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA. Argonne Natl Lab, Div Energy Syst, Waste Management & Bioengn Sect, Argonne, IL 60439 USA. RP Parulekar, SJ (reprint author), IIT, Dept Environm Chem & Engn, Chicago, IL 60616 USA. NR 47 TC 29 Z9 29 U1 2 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0376-7388 J9 J MEMBRANE SCI JI J. Membr. Sci. PD APR 1 PY 1998 VL 141 IS 1 BP 75 EP 89 DI 10.1016/S0376-7388(97)00292-5 PG 15 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA ZC917 UT WOS:000072632000007 ER PT J AU White, DC Flemming, CA Leung, KT Macnaughton, SJ AF White, DC Flemming, CA Leung, KT Macnaughton, SJ TI In situ microbial ecology for quantitative appraisal, monitoring, and risk assessment of pollution remediation in soils, the subsurface, the rhizosphere and in biofilms SO JOURNAL OF MICROBIOLOGICAL METHODS LA English DT Article DE natural attenuation; risk assessment; microbial ecology; signature biomarker analysis ID HYDROXY FATTY-ACIDS; GRAM-NEGATIVE BACTERIA; COMMUNITY STRUCTURE; HIGH-SOLIDS; NUTRITIONAL-STATUS; VIBRIO-CHOLERAE; DEEP SUBSURFACE; RIBOSOMAL-RNA; SEDIMENTS; BIOMASS AB Numerous studies have established a relationship between soil, sediment, surface biofilm and subsurface contaminant pollution and a marked impact on the in situ microbial community in both microcosms and in the field. The impact of pollution on the in situ microbial community can now be quantitatively measured by molecular 'fingerprinting' using 'signature' biomarkers. Such molecular fingerprinting methods can replace classical microbiological techniques that relied on isolation and subsequent growth of specific microbes from the in situ microbial community. Classical methods often revealed less than 1% of the extant microbial communities. Molecular fingerprinting provides a quantitative measure of the in situ viable microbial biomass, community composition, nutritional status, relative frequency of specific functional genes, nucleic acid polymers of specific microbes, and, in some cases, the community metabolic activity can be inferred. Current research is directed at establishing correlations between contaminant disappearance, diminution in toxicity, and the return of the viable biomass, community composition, nutritional status, gene patterns of the in situ microbial community towards that of the uncontaminated soil, sediment or subsurface material with the original uncontaminated microniche environments. Compared to the current reliance on disappearance of pollutants and associated potentially toxic products for detection of effective and quantitative bioremediation, assessment of the in situ microbial community will be an additional and possibly more convincing risk assessment tool. The living community tends to accumulate and replicate toxic insults through multiple interactions within the community, which may then effect viable biomass, community composition, nutritional status, community metabolic activities, and specific nucleic acid polymer patterns. (C) 1998 Elsevier Science B.V. C1 Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Microbial Insights Inc, Rockford, TN 37953 USA. RP White, DC (reprint author), Univ Tennessee, Ctr Environm Biotechnol, Knoxville, TN 37932 USA. EM milipids@aol.Com NR 61 TC 70 Z9 83 U1 2 U2 19 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-7012 J9 J MICROBIOL METH JI J. Microbiol. Methods PD APR PY 1998 VL 32 IS 2 SI SI BP 93 EP 105 DI 10.1016/S0167-7012(98)00017-7 PG 13 WC Biochemical Research Methods; Microbiology SC Biochemistry & Molecular Biology; Microbiology GA ZW096 UT WOS:000074373600002 ER PT J AU Kilaas, R AF Kilaas, R TI Optimal and near-optimal filters in high-resolution electron microscopy SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article; Proceedings Paper CT International Workshop on Image Analysis Methods in Quantitative TEM CY MAR 09-14, 1997 CL TEGERNSEE, GERMANY DE amorphous; average background subtraction filter; crystalline; noise reduction; Wiener filter ID HREM AB Two filters for improving the visibility of crystalline material in the presence of amorphous surface contamination layers in high-resolution electron microscope images call be constructed automatically from the information present in the Fourier transform of the recorded image. The recorded signal is considered in the first approximation to be the sum of two signals which are uncorrelated in the frequency domain, By estimating the power spectrum of the signal from the amorphous layer, an optimized estimate for the desired signal is given by the Wiener filter. A second filter which uses the estimated amplitude of the amorphous signal to subtract out a background can be shown to be related to the Wiener filter. The two filters are applied to an experimental image of zeolite and the effects of the two filters are compared. C1 Ernest Orlando Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. RP Kilaas, R (reprint author), Ernest Orlando Lawrence Berkeley Natl Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. NR 10 TC 102 Z9 102 U1 1 U2 20 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD APR-MAY PY 1998 VL 190 BP 45 EP 51 DI 10.1046/j.1365-2818.1998.3070861.x PN 1-2 PG 7 WC Microscopy SC Microscopy GA ZJ831 UT WOS:000073258100006 ER PT J AU King, WE Campbell, GH Foiles, SM Cohen, D Hanson, KM AF King, WE Campbell, GH Foiles, SM Cohen, D Hanson, KM TI Quantitative HREM observation of the Sigma 11(113)/[(1)over-bar-10] grain-boundary structure in aluminium and comparison with atomistic simulation SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article; Proceedings Paper CT International Workshop on Image Analysis Methods in Quantitative TEM CY MAR 09-14, 1997 CL TEGERNSEE, GERMANY DE electron microscopy; high resolution; least squares; optimization; quantitative AB Quantitative high-resolution electron microscopy (QHREM) involves the detailed comparison of experimental high-resolution images with image simulation based on a model and weighted by the estimated uncertainty in the experimental results, For simple metals, such as Al, models have been systematically improved using nonlinear least-squares methods to obtain simulated images that are indistinguishable from experimental images within the experimental error, QHREM has been used to study the atomic structure of the Sigma 11(113)/[(1) over bar 10] in Al, In this paper, we focus on the method of refining electron-optical imaging parameters and atomic structure to bring the simulated HREM image into agreement with the experimental result to within the experimental error and thus yield a result more useful to the materials scientist. Uncertainties in fitted parameters are studied using the conditional probability distribution function. We discuss experimental results for atomic column locations compared with atomistic simulations of the structure of the grain boundary. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Sandia Natl Labs, Livermore, CA 94551 USA. Univ Minnesota, Dept Chem Engn & Mat Sci, Minneapolis, MN 55455 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP King, WE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RI Campbell, Geoffrey/F-7681-2010 NR 12 TC 20 Z9 20 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD APR-MAY PY 1998 VL 190 BP 131 EP 143 DI 10.1046/j.1365-2818.1998.3320899.x PN 1-2 PG 13 WC Microscopy SC Microscopy GA ZJ831 UT WOS:000073258100013 ER PT J AU Nellist, PD Pennycook, SJ AF Nellist, PD Pennycook, SJ TI Accurate structure determination from image reconstruction in ADF STEM SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article; Proceedings Paper CT International Workshop on Image Analysis Methods in Quantitative TEM CY MAR 09-14, 1997 CL TEGERNSEE, GERMANY DE ADF; image reconstruction; incoherent imaging; probe reconstruction; STEM; structure determination ID TRANSMISSION ELECTRON-MICROSCOPY; CRYSTAL DEFECT STRUCTURES; SCATTERED ELECTRONS; SIMULATED EVOLUTION; HREM IMAGES; RESOLUTION; RETRIEVAL; GERMANIUM AB Annular dark-field (ADF) imaging in a scanning transmission electron microscope results in direct structure images of the atomic configuration of the specimen. Since such images are almost perfectly incoherent they can be treated as a convolution between a point-spread function, which is simply the intensity of the illuminating electron probe, and a sharply peaked object function that represents the projected structure of the specimen. Knowledge of the object function for an image region of perfect crystal allows the point-spread function to be directly determined for that image. We examine how the object function for an image can then be reconstructed using a Wiener filter, the CLEAN algorithm and a maximum entropy reconstruction, Prior information is required to perform a reconstruction, and we discuss what nature of prior information is suitable for ADF imaging. C1 Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Nellist, PD (reprint author), Univ Cambridge, Cavendish Lab, Madingley Rd, Cambridge CB3 0HE, England. NR 28 TC 69 Z9 69 U1 0 U2 15 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD APR-MAY PY 1998 VL 190 BP 159 EP 170 DI 10.1046/j.1365-2818.1998.3260881.x PN 1-2 PG 12 WC Microscopy SC Microscopy GA ZJ831 UT WOS:000073258100015 ER PT J AU Merkle, KL Csencsits, R Rynes, KL Withrow, JP Stadelmann, PA AF Merkle, KL Csencsits, R Rynes, KL Withrow, JP Stadelmann, PA TI The effect of three-fold astigmatism on measurements of grain boundary volume expansion by high-resolution transmission electron microscopy SO JOURNAL OF MICROSCOPY-OXFORD LA English DT Article; Proceedings Paper CT International Workshop on Image Analysis Methods in Quantitative TEM CY MAR 09-14, 1997 CL TEGERNSEE, GERMANY DE grain boundaries; HREM; rigid-body displacement; three-fold astigmatism; volume expansion ID RIGID-BODY DISPLACEMENTS; 3-FOLD ASTIGMATISM; PARAMETERS; SIMULATION; METALS; HREM AB In the absence of high-order aberrations, the lattice fringe technique should allow measurement of grain boundary rigid-body displacements to accuracies about an order of magnitude better than the point-to-point resolution of the transmission electron microscope. The three-fold astigmatism, however, introduces shifts of the lattice fringe pattern that depend on the orientation of the lattice relative to the direction of the three-fold astigmatism and thus produces an apparent shift between the two grains bordering the grain boundary. By image simulation of grain boundary model structures, the present paper explores the effect of these extraneous shifts on grain boundary volume expansion measurements, It is found that the shifts depend, among others, on zone axis direction and the magnitude of the lattice parameter. For many grain boundaries of interest, three-fold astigmatism correction to better than 100 nm appears necessary to achieve the desired accuracies. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Ecole Polytech Fed Lausanne, CIME, MXC, CH-1015 Lausanne, Switzerland. RP Merkle, KL (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 15 TC 22 Z9 22 U1 0 U2 3 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0022-2720 J9 J MICROSC-OXFORD JI J. Microsc.-Oxf. PD APR-MAY PY 1998 VL 190 BP 204 EP 213 DI 10.1046/j.1365-2818.1998.2890841.x PN 1-2 PG 10 WC Microscopy SC Microscopy GA ZJ831 UT WOS:000073258100020 ER PT J AU Schlosser, R Hutchinson, M Joseffer, S Rusinek, H Saarimaki, A Stevenson, J Dewey, SL Brodie, JD AF Schlosser, R Hutchinson, M Joseffer, S Rusinek, H Saarimaki, A Stevenson, J Dewey, SL Brodie, JD TI Functional magnetic resonance imaging of human brain activity in a verbal fluency task SO JOURNAL OF NEUROLOGY NEUROSURGERY AND PSYCHIATRY LA English DT Article DE verbal fluency; sex; functional magnetic resonance imaging (fMRI) ID WORD GENERATION; FRONTAL-CORTEX; LANGUAGE; ACTIVATION; PET; MRI AB Objectives-Functional MRI (fMRI) holds the promise of non-invasive mapping of human brain function in both health and disease. Yet its sensitivity and reliability for mapping higher cognitive function are still being determined, Using verbal fluency as a task, the objective was to ascertain the consistency of fMRI on a conventional scanner for determining the anatomic substrate of language between subjects and between sexes. Comparison was made with previous PET studies. Methods-Using a 1.5 Tesla magnet and an echoplanar pulse sequence, whole brain fMRI was obtained from 12 normal right handed subjects (6 males and 6 females) as they performed a verbal fluency task. Results-A broadly consistent pattern of response was seen across subjects. Areas showing activation changes included the left prefrontal cortex and right cerebellum, in agreement with previous PET O-15-H2O studies, In addition, significantly decreased responses were seen in the posterior cingulate and over an extensive area of mesial and dorsolateral parietal and superior temporal cortices. The male cohort showed a slight asymmetry of parietal deactivation, with more involvement on the right, whereas the female cohort showed a small region of activation in the right orbitofrontal cortex. There were individual task related regional changes in all 12 subjects with the area showing the most significant change being the left prefrontal cortex in all cases. Conclusions-Magnetic resonance scanners of conventional field strength can provide functional brain mapping data with a sensitivity at least that of PET. Activation was seen in left prefrontal and right cerebellar regions, as with PET. However, decremental responses were seen over a much larger area of the posterior cortex than had been anticipated by prior studies. The ability to see a response in each subject individually suggests that fMRI may be useful in the preinterventional mapping of pathological states, and offers a non-invasive alternative to the Wada test for assessment of hemispheric dominance. There were no gross differences int the pattern of activation between male and female subjects. C1 NYU, Med Ctr, Dept Psychiat, New York, NY 10016 USA. NYU, Med Ctr, Dept Neurol, New York, NY 10016 USA. NYU, Med Ctr, Dept Radiol, New York, NY 10016 USA. NYU, Med Ctr, Gen Clin Res Ctr, New York, NY 10016 USA. Brookhaven Natl Lab, Dept Chem, Upton, NY 10973 USA. RP Brodie, JD (reprint author), NYU, Med Ctr, Dept Psychiat, 550 1St Ave, New York, NY 10016 USA. RI Schlosser, Ralf/F-2822-2010 FU NCRR NIH HHS [MO1 RR-0096]; NIMH NIH HHS [MH 47277, MH 49165] NR 26 TC 256 Z9 257 U1 5 U2 10 PU BRITISH MED JOURNAL PUBL GROUP PI LONDON PA BRITISH MED ASSOC HOUSE, TAVISTOCK SQUARE, LONDON WC1H 9JR, ENGLAND SN 0022-3050 J9 J NEUROL NEUROSUR PS JI J. Neurol. Neurosurg. Psychiatry PD APR PY 1998 VL 64 IS 4 BP 492 EP 498 DI 10.1136/jnnp.64.4.492 PG 7 WC Clinical Neurology; Psychiatry; Surgery SC Neurosciences & Neurology; Psychiatry; Surgery GA ZJ938 UT WOS:000073268800013 PM 9576541 ER PT J AU Pekala, RW Farmer, JC Alviso, CT Tran, TD Mayer, ST Miller, JM Dunn, B AF Pekala, RW Farmer, JC Alviso, CT Tran, TD Mayer, ST Miller, JM Dunn, B TI Carbon aerogels for electrochemical applications SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE carbon; aerogel; electrodes ID CAPACITIVE DEIONIZATION; ORGANIC AEROGELS; ENERGY-STORAGE; ELECTRODES; FORMALDEHYDE; RESORCINOL; BEHAVIOR AB A major advantage of highly crosslinked, organic aerogels is the ability to transform many of these materials into electrically conductive carbon aerogels. Carbon aerogels have been formed as monoliths, microspheres, irregularly-shaped powders. and thin film composites. In all cases, the carbon aerogels retain their high surface area (400-800 m2/g) and ultrafine cell/pore size (<100 nm). Carbon aerogels are bring examined as electrodes for double lever capacitors, pseudocapacitors, and capacitive deionization units. This paper examines the synthesis, structure-property relationships, and performance of carbon aerogel electrodes used in electrochemical applications. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. PolyStor, Dublin, CA 94568 USA. Univ Calif Los Angeles, Dept Mat Sci & Engn, Los Angeles, CA 90095 USA. RP Pekala, RW (reprint author), PPG Ind, 440 Coll Pk Dr, Monroeville, PA 15146 USA. NR 25 TC 323 Z9 362 U1 28 U2 230 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 74 EP 80 DI 10.1016/S0022-3093(98)00011-8 PG 7 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600015 ER PT J AU Gross, J Coronado, PR Hrubesh, LW AF Gross, J Coronado, PR Hrubesh, LW TI Elastic properties of silica aerogels from a new rapid supercritical extraction process SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE silica aerogel; tetramethoxysilane; elasticity; supercritical condition AB Silica aerogels were produced by a new process from tetramethoxysilane (TMOS) with ammonia as base catalyst. The process involves pouring the liquid sol in a stainless steel mold and immediately heating to supercritical conditions. Gelation and aging occur during heating and reaction rates are high due to high average temperatures. The gel fills the container completely, which enables relatively fast venting of the supercritical fluid by providing a constraint for swelling and failure of the gel monolith. The whole process can be completed within 1 h. Longitudinal and shear moduli were measured in the dried aerogels by ultrasonic velocity measurements both as a function of chemical composition of the original sol. and of position in the aerogel. The sound velocity exhibits marked maxima close to the edges of the cylindrical, where the fluid left during venting. Specimens with high catalyst concentration and high water: TMOS ratio exhibited higher average moduli. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Princeton Univ, Dept Civil Engn & Operat Res, Princeton, NJ 08544 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Gross, J (reprint author), Princeton Univ, Dept Civil Engn & Operat Res, Eng Quad E-228, Princeton, NJ 08544 USA. NR 6 TC 13 Z9 14 U1 1 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 282 EP 286 DI 10.1016/S0022-3093(98)00045-3 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600055 ER PT J AU Hunt, AJ AF Hunt, AJ TI Light scattering for aerogel characterization SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE light scattering; aerogel; microstructure ID SILICA AEROGELS AB Light scattering is a useful tool to evaluate aerogel clarity, study its structure, pore size, mechanical strain, and examine the modes of sol-gel evolution that determine its microstructure. Ultraviolet-visible transmission spectroscopy can be used to study the wavelength dependent scattering to readily compare aerogels of differing origins, thickness, and to evaluate effects of residual contaminants. Infrared reflectance measurements can be used to determine the effective real and imaginary indices of refraction of porous aerogel materials for material property and radiant heat transfer studies. Measurements of scattering at a fixed angle can be used for quality control, to evaluate sources of scattering, and study inhomogeneities. Measurement of the Mueller matrix (describing the 16-element angle-dependent transformation of intensity and polarization of incident to scattered light) provides information about the anisotropy, large pore fraction, induced stresses, microstructure and inhomogeneities in the aerogel. The time evolution of scattering before and after gel formation gives information. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hunt, AJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 10 TC 17 Z9 17 U1 1 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 303 EP 306 DI 10.1016/S0022-3093(98)00048-9 PG 4 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600059 ER PT J AU Hunt, AJ Ayers, MR AF Hunt, AJ Ayers, MR TI Light scattering studies of UV-catalyzed gel and aerogel structure SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE aerogel; ultraviolet; sol-gel; light scattering ID SILICA AEROGELS; SOL AB The skeletal structure of aerogel is determined before, during, and after the gel is formed. Supercritical drying of aerogel largely preserves the pore structure that is determined near the time of gelation. To better understand gel-formation mechanisms, measurements of the time evolution of light scattering in a series of gels prepared without conventional acid or base catalysis were conducted. Ultraviolet light was used to catalyze the formation of silica gels made from hydrolysis of tetraethylorthosilicate and partly prehydrolyzed tetraethylorthosilicate in ethanol. Time evolution of light scattering provides information regarding the rate and geometrical nature of the assembly of the primary silica particles formed in the sol. UV-catalyzed gels show volumetric growth typical of acid-catalyzed gels, except when UV exposure is discontinued at the gel point, where gels then show linear chain formation typical of base-catalyzed gels. Long-term UV exposure leads to coarsening of the pore network, a decrease in the clarity of the aerogel, and an increase in the surface area of the aerogel. Additionally, UV exposure up to the gel point leads to increased crystallinity in the final aerogel. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Hunt, AJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 9 TC 6 Z9 6 U1 2 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 325 EP 329 DI 10.1016/S0022-3093(98)00132-X PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600063 ER PT J AU Hrubesh, LW AF Hrubesh, LW TI Aerogel applications SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE aerogel; property; dielectric ID MONOLITHIC SILICA AEROGEL; LOW-DENSITY XEROGELS; LOW-K-DIELECTRICS; CHERENKOV COUNTERS; ACOUSTIC PROPERTIES; HE-3-HE-4 MIXTURE; AMBIENT-PRESSURE; FABRICATION; LIQUID-HE-4; CATALYSTS AB Aerogel materials possess a wide variety of exceptional properties, hence a striking number of applications have developed for them. Many of the commercial applications of aerogels such as catalysts, thermal insulation, windows, and particle detectors are under development and new applications have been publicized since the ISA4 Conference in 1994. e.g., supercapacitors, insulation for heat storage in automobiles, electrodes for capacitive deionization, etc. More applications are evolving as the scientific and engineering community becomes familiar with the unusual and exceptional physical properties of aerogels. Ln addition to growing commercial applications of aerogels, there are also scientific and technical applications, as well. This paper discusses a variety of technical applications of aerogels. It reports current technical applications under development for which several types of aerogels are formed in custom sizes and shapes. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Hrubesh, LW (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-322, Livermore, CA 94550 USA. EM hrubesh@llal.gov NR 93 TC 284 Z9 337 U1 20 U2 200 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1-3 BP 335 EP 342 DI 10.1016/S0022-3093(98)00135-5 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600065 ER PT J AU Ayers, MR Hunt, AJ AF Ayers, MR Hunt, AJ TI Molecular oxygen sensors based on photoluminescent silica aerogels SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE aerogel; oxygen molecules; oxygen concentration; photoluminescence; air pressure ID METAL-COMPLEXES; POLYMER SUPPORTS; LUMINESCENCE; MATRICES AB Photoluminescent silica aerogel acts as the active element of an optical sensor for molecular oxygen. The luminescent aerogel is prepared by the action of energized reducing gases on a standard silica aerogel. Intensity of aerogel photoluminescence decreases as the collision frequency between oxygen molecules and the luminescent carriers in the aerogel matrix increases. This behavior is a characteristic of many photoluminescent materials and arises from a transfer of energy from the aerogel to surrounding oxygen molecules. A sensor for oxygen concentration or air pressure can therefore be simply constructed utilizing an ultraviolet source for excitation and a suitable detector for the emitted visible signal. Stern-Volmer quenching constants for the aerogel sensing element are 1.55 X 10(-2) Torr(-1) for hydrophilic aerogel and 2.4 X 10(-3) Torr(-1) for hydrophobic aerogel. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Ayers, MR (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 11 TC 20 Z9 22 U1 2 U2 14 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 343 EP 347 DI 10.1016/S0022-3093(98)00051-9 PG 5 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600066 ER PT J AU Tillotson, TM Hrubesh, LW Simpson, RL Lee, RS Swansiger, RW Simpson, LR AF Tillotson, TM Hrubesh, LW Simpson, RL Lee, RS Swansiger, RW Simpson, LR TI Sol-gel processing of energetic materials SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article; Proceedings Paper CT 5th International Symposium on Aerogels CY SEP 08-10, 1997 CL MONTPELLIER, FRANCE SP Univ Montpellier, CNRS, Reg Languedoc Roussillon, Ctr Etud Commissariat Energie Atom Bruyeres Chatel, Ctr Etud Commissariat Energie Atom Vahrho DE sol-gel; detonators; pellets ID SILICA AEROGEL AB Traditional manufacturing of energetic materials involves processing of granular solids. One application is the production of detonators where powders of energetic material and a binder are typically mixed and compacted at high pressure to make pellets. Performance properties are strongly dependent on particle size distribution, surface area of its constituents, homogeneity of the mix, and void volume. The goal is to produce detonators with fast energy release rate that are insensitive to unintended initiation. Preparation of detonators from xerogel molding powders and aerogels, and comparison with materials produced by state-of-the-art technology are described. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. Univ Calif Lawrence Livermore Natl Lab, Energet Mat Ctr, Livermore, CA 94550 USA. RP Tillotson, TM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. NR 11 TC 61 Z9 74 U1 2 U2 12 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 225 IS 1 BP 358 EP 363 DI 10.1016/S0022-3093(98)00055-6 PG 6 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZY627 UT WOS:000074642600069 ER PT J AU Anderson, TS Magruder, RH Kinser, DL Wittig, JE Zuhr, RA Thomas, DK AF Anderson, TS Magruder, RH Kinser, DL Wittig, JE Zuhr, RA Thomas, DK TI AG : CD and CD : AG implantations into high purity silica SO JOURNAL OF NON-CRYSTALLINE SOLIDS LA English DT Article ID SEQUENTIAL ION-IMPLANTATION; OPTICAL-PROPERTIES; NONLINEAR OPTICS; METAL COLLOIDS; ABSORPTION; GLASS; PARTICLES; RESONANCE; CU AB Silica composites containing nanometer dimension colloids were fabricated by implantation of Ag ions followed by Cd ions, and by implantation of Cd ions followed by Ag ions. These samples were characterized using transmission electron microscopy and optical spectroscopy. Doses used for the sequential implantations were 6 x 10(16) ions/cm(2) of Ag and Cd in a 1 to 1 ratio. Single element colloids were also fabricated by implantation of Ag or Cd using the same nominal dose and implantation energy as the sequential implantations. Sequential implantation of Ag and Cd leads to the formation of multi-component metal nanoclusters and elemental nanoclusters. Different microstructures were obtained depending on the order of implantation. Optical responses are consistent with results expected from effective medium theory. (C) 1998 Elsevier Science B.V. C1 Vanderbilt Univ, Dept Appl & Engn Sci, Nashville, TN 37235 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Anderson, TS (reprint author), Vanderbilt Univ, Dept Appl & Engn Sci, 221 Kirkland Hall, Nashville, TN 37235 USA. NR 23 TC 16 Z9 18 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3093 J9 J NON-CRYST SOLIDS JI J. Non-Cryst. Solids PD APR PY 1998 VL 224 IS 3 BP 299 EP 306 DI 10.1016/S0022-3093(97)00469-9 PG 8 WC Materials Science, Ceramics; Materials Science, Multidisciplinary SC Materials Science GA ZL371 UT WOS:000073426200012 ER PT J AU Hess, NJ Weber, WJ Conradson, SD AF Hess, NJ Weber, WJ Conradson, SD TI X-ray absorption fine structure of aged, Pu-doped glass and ceramic waste forms SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID MULTIPLE-SCATTERING CALCULATIONS; RADIATION; URANIUM; SPECTRA; DAMAGE; ZIRCON; EDGE AB X-ray absorption spectroscopic (XAS) studies were performed on three compositionally identical, Pu-doped, borosilicate glasses prepared 15 years ago at different alpha-activities by varying the Pu-239/Pu-238 isotopic ratio. The resulting alpha-activities ranged from 1.9 x 10(7) to 4.2 x 10(9) Bq/g and have current, accumulated doses between 8.8 x 10(15) to 1.9 x 10(18) alpha-decays/g. Two ceramic, polycrystalline zircon (ZrSiO4) samples prepared 16 years ago with 10.0 wt% Pu was also investigated. Varying the Pu-239/Pu-238 isotopic ratio in these samples resulted in alpha-activities of 2.5 x 10(8) and 5.6 x 10(10) Bq/g and current, accumulated doses of 1.2 x 10(17) and 2.8 x 10(19) alpha-decays/g. The multicomponent composition of the waste forms permitted XAS investigations at six absorption edges for the borosilicate glass and at three absorption edges for the polycrystalline zircons. For both waste forms, analysis of extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectra indicates that the local environment around the cations exhibits different degrees of disorder as a result of the accumulated alpha-decay dose. In general, cations with short cation-oxygen bonds show little effect from self-radiation whereas cations with long cation-oxygen bonds show a greater degree of disorder with accumulated alpha-decay dose. (C) 1998 Elsevier Science B.V. C1 Pacific NW Lab, Richland, WA 99352 USA. Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hess, NJ (reprint author), Pacific NW Lab, POB 999,MS K2-44, Richland, WA 99352 USA. EM nj_hess@pnl.gov RI Weber, William/A-4177-2008; OI Weber, William/0000-0002-9017-7365; Hess, Nancy/0000-0002-8930-9500 NR 28 TC 28 Z9 29 U1 1 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD APR PY 1998 VL 254 IS 2-3 BP 175 EP 184 DI 10.1016/S0022-3115(98)00011-7 PG 10 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA ZR725 UT WOS:000074007500008 ER PT J AU Gong, WL Wang, LM Ewing, RC Vernaz, E Bates, JK Ebert, WL AF Gong, WL Wang, LM Ewing, RC Vernaz, E Bates, JK Ebert, WL TI Analytical electron microscopy study of surface layers formed on the French SON68 nuclear waste glass during vapor hydration at 200 degrees C SO JOURNAL OF NUCLEAR MATERIALS LA English DT Article ID CRYSTAL-STRUCTURE; THIN-SECTIONS; ENVIRONMENT; TOBERMORITE AB Extensive solid-state characterization (AEM/SEM/HRTEM) was completed on six SON68 (inactive R7T7) waste glasses which were alter ed in the presence of saturated water vapor (200 degrees C) for 22, 91, 241, 908, 1000, 1013, and 1021 days. The samples were examined by AEM in cross-section (lattice-fringe imaging, micro-diffraction, and quantitative thin-film EDS analysis). The glass monoliths were invariably covered by a thin altered rind, and the surface layer thickness increased with increasing time of reaction, ranging from 0.5 to 30 mu m in thickness. Six distinctive zones, based on phase chemistry and microstructure, were distinguished within the well-developed surface layers. Numerous crystalline phases such as analcime, gyrolite, tobermorite, apatite, and weeksite were identified on the surfaces of the reacted glasses as precipitates. The majority of the surface layer volume was composed of two basic structures that are morphologically and chemically distinct: The A-domain consisted of well-crystallized fibrous smectite aggregates; and the B-domain consisted of poorly-crystallized regions containing smectite, possibly montmorillonite, crystallites and a ZrO2-rich amorphous silica matrix. The retention of the rare-earth elements, Mo, and Zr mostly occurred within the B-domain; while transition metal elements, such as Zn, Cr, Ni, Mn, and Fe, were retained in the A-domain. The element partitioning among A-domains and B-domains and recrystallization of the earlier-formed B-domains into the A-domain smectites were the basic processes which have controlled the chemical and structural evolution of the surface layer. The mechanism of surface layer formation during vapor hydration are discussed based on these cross-sectional AEM results. (C) 1998 Elsevier Science B.V. C1 Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. CEA, VALRHO, F-30205 Bagnols, France. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Gong, WL (reprint author), Univ New Mexico, Dept Earth & Planetary Sci, Albuquerque, NM 87131 USA. EM wgong@unm.edu NR 39 TC 33 Z9 33 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0022-3115 J9 J NUCL MATER JI J. Nucl. Mater. PD APR PY 1998 VL 254 IS 2-3 BP 249 EP 265 DI 10.1016/S0022-3115(97)00349-8 PG 17 WC Materials Science, Multidisciplinary; Nuclear Science & Technology SC Materials Science; Nuclear Science & Technology GA ZR725 UT WOS:000074007500017 ER PT J AU Sonnenthal, EL McBirney, AR AF Sonnenthal, EL McBirney, AR TI The Skaergaard Layered Series. Part IV. Reaction-transport simulations of foundered blocks SO JOURNAL OF PETROLOGY LA English DT Article DE assimilation; convection; reaction-transport modeling; Skaergaard Intrusion; solidification zones ID MAGMATIC SILICATE LIQUIDS; EAST GREENLAND; HYDROTHERMAL SYSTEMS; CRYSTAL DISSOLUTION; INTRUSION; COMPACTION; MODEL; MELT; DIFFERENTIATION; CONVECTION AB During the middle stages of crystallization of the Skaergaard Layered Series large numbers of blocks became detached from the Upper Border Series and settled into the mush of crystals on the floor. It has been recognized for some time that these blocks now have compositions and textures that differ markedly from those of the units from which they came. They tend to be more plagioclase rich and seem to have lost mafic components to the surrounding gabbro. Numerical simulations coupling crystallization, melting, and heat and mass transfer for a multicomponent system show how the blocks reacted with the mush in which they were emplaced. Enhanced cooling and crystallization of a compositionally stratified mush adjacent to the blocks resulted in patterns of melt compositions similar to those of layering around the blocks. Volume changes during crystallization and melting induced convection of the interstitial melt leading to changes in the bulk compositions of the blocks and the surrounding mush. Inhomogeneities such as inclusions are likely to facilitate the onset of compositional convection in a chemically stratified solidification zone. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Oregon, Dept Geol Sci, Eugene, OR 97403 USA. RP Sonnenthal, EL (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, MS90-1116, Berkeley, CA 94720 USA. EM elsonnenthal@lbl.gov RI Sonnenthal, Eric/A-4336-2009 NR 58 TC 13 Z9 13 U1 0 U2 3 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0022-3530 J9 J PETROL JI J. Petrol. PD APR PY 1998 VL 39 IS 4 BP 633 EP 661 DI 10.1093/petrology/39.4.633 PG 29 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA ZH446 UT WOS:000073111000003 ER PT J AU Rzyman, K Moser, Z Watson, RE Weinert, M AF Rzyman, K Moser, Z Watson, RE Weinert, M TI Enthalpies of formation of AlNi: Experiment versus theory SO JOURNAL OF PHASE EQUILIBRIA LA English DT Article ID INTERMETALLIC COMPOUNDS; CALORIMETRIC DETERMINATION; THERMODYNAMIC PROPERTIES; PHASE-DIAGRAM; SYSTEM AB The thermodynamic properties of the B2 AINi phase have been revisited with calorimetric and a priori theoretical estimates of the enthalpy of formation of the stoichiometric compound. The calorimetric study has surveyed the temperature dependence of the enthalpy of formation and extrapolated it to zero temperature (for which the a priori estimates have been made),while the theoretical estimate explores the consequences of an apparent error in local density-based potentials in yielding the magnetic contribution to the reference energy of Ni metal, The present experimental value, extrapolated to 0 K, is 65.915 kJ/g-atom while the local density-based calculated value is 67.5 kJ/g-atom. These are in accord with each other and with much, but not all, the previous experimental data. An estimate of the error in the local density magnetic energy was made by comparing experimental and calculated heats for nonmagnetic Fe compounds, where the energy and its associated error are much larger, and scaling the result to Ni. This yields a "corrected" theoretical heat of 66 kT/g-atom. C1 Polish Acad Sci, Inst Met & Mat Sci, PL-30059 Krakow, Poland. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Rzyman, K (reprint author), Polish Acad Sci, Inst Met & Mat Sci, Reymonta St 25, PL-30059 Krakow, Poland. EM nmmoser@al.imim-pan.krakow.pl RI MOSER, Zbigniew/A-6228-2008 NR 35 TC 35 Z9 35 U1 0 U2 3 PU ASM INTERNATIONAL PI MATERIALS PARK PA SUBSCRIPTIONS SPECIALIST CUSTOMER SERVICE, MATERIALS PARK, OH 44073-0002 USA SN 1054-9714 J9 J PHASE EQUILIB JI J. Phase Equilib. PD APR PY 1998 VL 19 IS 2 BP 106 EP 111 DI 10.1361/105497198770342562 PG 6 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA ZH318 UT WOS:000073095800005 ER PT J AU Lepre, AM Sutherland, JC Trunk, JG Sutherland, BM AF Lepre, AM Sutherland, JC Trunk, JG Sutherland, BM TI A robust, inexpensive filter for blocking UVC radiation in broad-spectrum 'UVB' lamps SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY LA English DT Article DE UV radiation; UV filter; environmental photobiology; cyclobutyl pyrimidine dimer ID PYRIMIDINE DIMERS; STRAND BREAKS; DNA-DAMAGE; QUANTITATION; ELECTROPHORESIS; GELS AB Accurate studies of the biological effects of UVB radiation require suitable laboratory sources. Lamps labeled as WE sources often emit UVC radiation that contributes significantly to the levels of DNA damage. The WC from an unfiltered WE source produced more pyrimidine dimers in soybean DNA than a lamp filtered by a Pyrex dish that removes wavelengths of < 280 nm. Calculations based on action spectra and on the emission spectra of unfiltered lamps indicate that UVC contributes similar to 13%, 4% and similar to 1% of the total dimers induced in unshielded cells or DNA, alfalfa cotyledons, and human skin, respectively. Further, relative to a Pyrex dish-filtered lamp, an unfiltered lamp would produce similar to 7-, 2.4- or 2.8-fold more dimers in these three biological systems. We report here that a Pyrex dish provides an effective, stable, robust and inexpensive filter for reducing or excluding the contribution of UVC to damage induced by broad-spectrum 'UVB' lamps. (C) 1998 Published by Elsevier Science S.A. C1 Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. RP Sutherland, BM (reprint author), Brookhaven Natl Lab, Dept Biol, Upton, NY 11973 USA. NR 17 TC 4 Z9 4 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1011-1344 J9 J PHOTOCH PHOTOBIO B JI J. Photochem. Photobiol. B-Biol. PD APR PY 1998 VL 43 IS 1 BP 34 EP 40 DI 10.1016/S1011-1344(98)00079-7 PG 7 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA ZQ840 UT WOS:000073908300004 PM 9639912 ER PT J AU Burakovsky, L Goldman, T Horwitz, LP AF Burakovsky, L Goldman, T Horwitz, LP TI New mass relation for meson 25-plet SO JOURNAL OF PHYSICS G-NUCLEAR AND PARTICLE PHYSICS LA English DT Article ID ANTIQUARK POTENTIAL MODELS; GLUON STRING MODEL; DUAL-PARTON MODEL; E+E ANNIHILATION; INCLUSIVE SPECTRA; NARROW RESONANCE; HIGH-ENERGIES; QUARK; DISCOVERY AB By assuming the existence of (quasi)-linear Regge trajectories for 25-plet mesons in the low-energy region, we derive a new, 14th power, meson mass relation. This relation may be reduced to a quadratic Gell-Mann-Okubo-type formula by fitting the values of the Regge slopes of these (quasi)-linear trajectories. Such a formula holds with an accuracy of similar to 2% for vector mesons, and also suggests that the quantum number I(J(p)) = 1/2 (2(+)) should be assigned to both the B-J(5732) and B-sJ(5850) mesons discovered recently. We also discuss reasons for the failure of group theory to produce correct mass relations for heavy quarkonia. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Bar Ilan Univ, Dept Phys, Ramat Gan, Israel. RP Burakovsky, L (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS B285, Los Alamos, NM 87545 USA. NR 63 TC 16 Z9 16 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0954-3899 J9 J PHYS G NUCL PARTIC JI J. Phys. G-Nucl. Part. Phys. PD APR PY 1998 VL 24 IS 4 BP 771 EP 778 DI 10.1088/0954-3899/24/4/009 PG 8 WC Physics, Nuclear; Physics, Particles & Fields SC Physics GA ZK495 UT WOS:000073327700009 ER PT J AU Withers, RL Evans, JSO Hanson, J Sleight, AW AF Withers, RL Evans, JSO Hanson, J Sleight, AW TI An in situ temperature-dependent electron and x-ray diffraction study of structural phase transitions in ZrV2O7 SO JOURNAL OF SOLID STATE CHEMISTRY LA English DT Article ID NEGATIVE THERMAL-EXPANSION AB A detailed electron diffraction study has been made of the ZrV2O7 member of the AM(2)O(7) family of displacively flexible framework structures and its temperature-dependent structural phase transformations. The phase below 77 degrees C corresponds to a primitive 3x3x3 superstructure phase of PA(3) over bar space group symmetry while the high temperature phase above 102 degrees C corresponds to the normal parent structure. The intervening intermediate phase is a complex incommensurately modulated phase characterized by (more than one) incommensurate primary modulation wave-vector in the close vicinity of 1/3[110]*. The cubic point group symmetry of this intervening incommensurate phase is shown to be lowered from cubic m3m. No corresponding metrical strain distortion can be detected. (C) 1998 Academic Press. C1 Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Oregon State Univ, Dept Chem, Corvallis, OR 97331 USA. RP Withers, RL (reprint author), Australian Natl Univ, Res Sch Chem, Canberra, ACT 0200, Australia. RI Hanson, jonathan/E-3517-2010; Evans, John/E-6345-2012; Withers, Ray/H-8309-2014 OI Evans, John/0000-0001-6305-6341; Withers, Ray/0000-0001-9017-2233 NR 17 TC 40 Z9 42 U1 1 U2 11 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-4596 J9 J SOLID STATE CHEM JI J. Solid State Chem. PD APR PY 1998 VL 137 IS 1 BP 161 EP 167 DI 10.1006/jssc.1998.7748 PG 7 WC Chemistry, Inorganic & Nuclear; Chemistry, Physical SC Chemistry GA ZR712 UT WOS:000074006200022 ER PT J AU Yang, MC Albright, JG Rard, JA Miller, DG AF Yang, MC Albright, JG Rard, JA Miller, DG TI Ternary solution mutual diffusion coefficients and densities of aqueous mixtures of sucrose with NaCl and sucrose with KCl at 25 degrees C SO JOURNAL OF SOLUTION CHEMISTRY LA English DT Article DE ternary solution diffusion; densities; sucrose; NaCl; KCl; Rayleigh interferometry ID RAYLEIGH INTERFEROMETRY; OSMOTIC COEFFICIENTS; CONCENTRATION RATIO; INTERDIFFUSION COEFFICIENTS; ELECTROLYTE-SOLUTIONS; MGCL2 CONCENTRATIONS; SULFURIC-ACID; WIDE-RANGE; NACL-MGCL2-H2O; INSTABILITIES AB Ternary solution isothermal mutual diffusion coefficients (interdiffusion coefficients) have been measured for aqueous mixtures of 0.250 mol-dm(-3) sucrose (component 1) with 0.5 and 1.0 mol-dm(-3) NaCl or with 0.5 and 1.0 mol-dm(-3) KCl (salt = component 2) at 25.00 degrees C using Rayleigh interferometry with computerized data acquisition. Densities were also measured. The volume-fixed diffusion coefficients (D-ij)(v) show the following characteristics. At all compositions (D-21)(v) is much larger than (D-12)(v) and (D-21)(v) is a fairly significant fraction (33 to 68%) of (D-11)(v). In addition, (D-12)(v) is slightly larger for mixtures containing NaCl than for those containing KCl at the same concentration, whereas (D-21)(v) is significantly larger for mixtures containing KCl. Values of (D-11)(v) are slightly larger for solutions containing KCl than for solutions containing NaCl. The observed trends imply that (D-21)(v) will probably exceed (D-11)(v) in both mixtures if concentrations of NaCl or of KCl are increased much further while maintaining the sucrose concentration at 0.250 mol-dm(-3). Finally, the solvent-fixed cross-term diffusion coefficients (D-12)(0) and (D-21)(0) are significantly larger than their corresponding (D-12)(v) and D-21)(v). C1 Texas Christian Univ, Dept Chem, Ft Worth, TX 76129 USA. Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Earth & Environm Sci Di, Livermore, CA 94550 USA. RP Yang, MC (reprint author), Texas Christian Univ, Dept Chem, TCU Box 298860, Ft Worth, TX 76129 USA. NR 69 TC 7 Z9 7 U1 0 U2 1 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0095-9782 J9 J SOLUTION CHEM JI J. Solut. Chem. PD APR PY 1998 VL 27 IS 4 BP 309 EP 329 DI 10.1023/A:1022623631416 PG 21 WC Chemistry, Physical SC Chemistry GA ZQ414 UT WOS:000073858800003 ER PT J AU Ovchinnikov, YN Wolf, SA Kresin, VZ AF Ovchinnikov, YN Wolf, SA Kresin, VZ TI Generation and detection of pairing bosons - A new method to determine the mechanism of superconductivity in the oxides SO JOURNAL OF SUPERCONDUCTIVITY LA English DT Article DE pairing mechanism; pairing boson AB We propose a new method to determine the coupling boson in the cuprate superconductors based on the generation and detection of the appropriate boson analogous to the experiments performed on the generation and detection of phonons by conventional BCS superconductors. The appropriate choice of substrate and junction detector will allow the unambiguous determination of the boson that is formed by the recombination of energy gap edge quasiparticles produced by excitations into the normal state of the cuprates. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. LD Landau Theoret Phys Inst, Moscow 11733V, Russia. RP Ovchinnikov, YN (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 11 TC 1 Z9 1 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0896-1107 J9 J SUPERCOND JI J. Supercond. PD APR PY 1998 VL 11 IS 2 BP 323 EP 325 DI 10.1023/A:1022604622449 PG 3 WC Physics, Applied; Physics, Condensed Matter SC Physics GA ZW706 UT WOS:000074439300023 ER PT J AU Zuo, QH Hjelmstad, KD AF Zuo, QH Hjelmstad, KD TI Bounds and approximations for elastodynamic wave speeds in tetragonal media SO JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA LA English DT Article AB This paper presents an analytical study of elastodynamic waves propagating along an arbitrary direction in anisotropic materials with tetragonal symmetry. Upper and lower bounds are developed on the wave speeds through an additive decomposition of the acoustic tensor into an associated hexagonal counterpart and a rank-one modification, the eigenproperties of which can be determined analytically. The bounds are obtained by applying the minimax property of eigenvalues. Linear approximations of the wave speeds are obtained from a first-order expansion of the eigenvalues of the acoustic tensor, with respect to a tetragonality index, about the value of that index for which tetragonal symmetry degenerates to hexagonal symmetry. A numerical example shows that the linear approximations agree remarkably well with the exact values of the wave speeds. (C) 1998 Acoustical Society of America. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Illinois, Dept Civil Engn, Urbana, IL 61801 USA. RP Zuo, QH (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. NR 21 TC 3 Z9 3 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0001-4966 J9 J ACOUST SOC AM JI J. Acoust. Soc. Am. PD APR PY 1998 VL 103 IS 4 BP 1727 EP 1733 DI 10.1121/1.421368 PG 7 WC Acoustics; Audiology & Speech-Language Pathology SC Acoustics; Audiology & Speech-Language Pathology GA ZJ991 UT WOS:000073274100005 ER PT J AU Tomlins, GW Routbort, JL Mason, TO AF Tomlins, GW Routbort, JL Mason, TO TI Oxygen diffusion in single-crystal zinc oxide SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID ZNO VARISTORS; INTERFACES AB The models used to describe zinc oxide-based varistors rely on diffusion and defect data obtained using techniques that have been replaced by more modern methods such as secondary ion mass spectrometry, We report values for oxygen diffusivities in undoped, single-crystal ZnO as a function of temperature and orientation. Evaporation was taken into consideration when analyzing experimental results. Within experimental error, the energetics of diffusion are isotropic, but are slightly faster in the c-direction, In comparing diffusion data from the literature, the intrinsic activation energy was estimated to be between 3.6 and 4.2 eV. Comparisons with recent theoretical calculations of relevant defect energies are discussed. C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Tomlins, GW (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Mason, Thomas/B-7528-2009 NR 47 TC 46 Z9 49 U1 2 U2 18 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD APR PY 1998 VL 81 IS 4 BP 869 EP 876 PG 8 WC Materials Science, Ceramics SC Materials Science GA ZJ248 UT WOS:000073195000007 ER PT J AU Zanoria, ES Blau, PJ AF Zanoria, ES Blau, PJ TI Effect of incidence angle on the impact-wear behavior of silicon nitride SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article AB Experiments were conducted by repeatedly hammering a silicon nitride (S3N4) ball on a polished different Si3N4 material at different incidence angles: 45 degrees, 60 degrees, 75 degrees, and 90 degrees, Material removal during impact was dominated by the delamination process, which involved abrasion and fracturing of the parent material, compaction of pulverized debris into a film, nucleation of cracks along the film/substrate interface, and lateral propagation of the interfacial cracks. The dependency of repeated impact wear on the incidence angle involved a combination of the effects of normal and tangential stresses on surface deformation, The contrasting influences of these stresses resulted in a minimization of impact wear of the polished Si3N4 material at incidence angles in the range of 60 degrees-75 degrees. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Zanoria, ES (reprint author), Caterpillar Inc, PPG, Peoria, IL 61656 USA. NR 9 TC 6 Z9 6 U1 1 U2 1 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD APR PY 1998 VL 81 IS 4 BP 901 EP 909 PG 9 WC Materials Science, Ceramics SC Materials Science GA ZJ248 UT WOS:000073195000011 ER PT J AU Rebillat, F Lamon, J Naslain, R Lara-Curzio, E Ferber, MK Besmann, TM AF Rebillat, F Lamon, J Naslain, R Lara-Curzio, E Ferber, MK Besmann, TM TI Interfacial bond strength in SiC/C/SiC composite materials, as studied by single-fiber push-out tests SO JOURNAL OF THE AMERICAN CERAMIC SOCIETY LA English DT Article ID BRITTLE-MATRIX COMPOSITES; PULL-OUT; REINFORCED COMPOSITES; MULTILAYERED INTERPHASES; CERAMIC COMPOSITES; GLASS-MATRIX; MECHANICS; ROUGHNESS; STRESSES; FRICTION AB The interfacial characteristics of SiC/C/SiC composites with different fiber-coating bond strengths have been investigated using single-fiber push-out tests. Previous studies have shown that weak or strong bonds can be obtained by using as-received or treated fibers, respectively, and that the stress-strain behavior is improved with the treated fibers. This effect results from multiple branching of the cracks within the interphase. The model used to extract interfacial characteristics from nanoindentation and microindentation tests does not consider the presence of an interphase. However, the results highlight the significant effect of the interphase on the interfacial parameters, as well as the effect of roughness along the sliding surfaces. For the composite with treated fibers, the uncommon upward curvature of the push-out curves is related to different modes of crack propagation in the interphase. Different techniques are required to analyze the interfacial properties, such as nanoindentation and microindentation with push-out and push-back tests. C1 Univ Bordeaux 1, LCTS, Lab Composites Thermostruct, SEP,CNRS,UMR 47, F-33600 Pessac, France. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Rebillat, F (reprint author), Univ Bordeaux 1, LCTS, Lab Composites Thermostruct, SEP,CNRS,UMR 47, F-33600 Pessac, France. NR 43 TC 48 Z9 48 U1 2 U2 17 PU AMER CERAMIC SOC PI WESTERVILLE PA 735 CERAMIC PLACE, PO BOX 6136, WESTERVILLE, OH 43081-6136 USA SN 0002-7820 J9 J AM CERAM SOC JI J. Am. Ceram. Soc. PD APR PY 1998 VL 81 IS 4 BP 965 EP 978 PG 14 WC Materials Science, Ceramics SC Materials Science GA ZJ248 UT WOS:000073195000020 ER PT J AU Festag, R Alexandratos, SD Joy, DC Wunderlich, B Annis, B Cook, KD AF Festag, R Alexandratos, SD Joy, DC Wunderlich, B Annis, B Cook, KD TI Effects of molecular entanglements during electrospray of high molecular weight polymers SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID IONIZATION MASS-SPECTROMETRY; MECHANISM; PARTICLES; DROPLETS; FISSION; IONS AB Concentration-dependent bimodal size distributions (comprised of single-molecule particles and multimolecule clusters) observed by microscopic examination of particles collected during electrospray (ES) of dilute solutions of high molecular weight polymers suggest that chain entanglement can interfere with the droplet subdivisions believed to be intrinsic to the electrospray process. The feasibility of such interference is discussed in the context of the spray model of Kebarle, along with its potential impact on the ES mass spectrometry of macromolecules. (C) 1998 American Society for Mass Spectrometry. C1 Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. Univ Tennessee, Dept Biochem & Cellular & Mol Biol, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Cook, KD (reprint author), Univ Tennessee, Dept Chem, Knoxville, TN 37996 USA. OI Cook, Kelsey/0000-0003-2053-3309 NR 24 TC 14 Z9 14 U1 3 U2 7 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD APR PY 1998 VL 9 IS 4 BP 299 EP 304 DI 10.1016/S1044-0305(98)00004-X PG 6 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA ZG151 UT WOS:000072971200006 PM 27518865 ER PT J AU Schultz, JC Hack, CA Benner, WH AF Schultz, JC Hack, CA Benner, WH TI Mass determination of megadalton-DNA electrospray ions using charge detection mass spectrometry SO JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY LA English DT Article ID MOLECULAR-WEIGHT DETERMINATION; INDUCED CONFORMATIONAL-CHANGES; IONIZATION; PROTEINS; POLYPEPTIDES; PEPTIDE; STATE; TIME AB Charge detection mass spectrometry (CD-MS) has been used to determine the mass of double-stranded, circular DNA and single-stranded, circular DNA in the range of 2500 to 8000 base pairs (1.5-5.0 MDa). Simultaneous measurement of the charge and velocity of an electrostatically accelerated ion allows a mass determination of the ion, with instrument calibration determined independently of samples. Positive ion mass spectra of electrosprayed commercial DNA samples supplied in tris(hydroxymethyl)ethylenediaminetetraacetic acid buffer, diluted in 50 vol. % acetonitrile, were obtained without cleanup of the sample. A CD mass spectrum constructed from 3000 ion measurements takes 10 min to acquire and yields the DNA molecular mass directly (mass resolution = 6). The data collected represent progress toward a more automatable alternative to sizing of DNA by gel electrophoresis. In addition to the mass spectra, CD-MS generates charge versus mass plots, which provide another means to investigate the creation and fate of large electrospray ions. (C) 1998 American Society for Mass Spectrometry. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. RP Schultz, JC (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, 1 Cyclotron Rd,MS 70A-3363, Berkeley, CA 94720 USA. NR 22 TC 49 Z9 49 U1 1 U2 16 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-0305 J9 J AM SOC MASS SPECTR JI J. Am. Soc. Mass Spectrom. PD APR PY 1998 VL 9 IS 4 BP 305 EP 313 DI 10.1016/S1044-0305(97)00290-0 PG 9 WC Chemistry, Analytical; Chemistry, Physical; Spectroscopy SC Chemistry; Spectroscopy GA ZG151 UT WOS:000072971200007 PM 27518866 ER PT J AU Mansour, AN Melendres, CA Wong, J AF Mansour, AN Melendres, CA Wong, J TI In situ X-ray absorption spectroscopic study of electrodeposited nickel oxide films during redox reactions SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID MULTIPLE-SCATTERING CALCULATIONS; FINE-STRUCTURE; QUADRIVALENT NICKEL; EDGE STRUCTURE; SPECTRA; QUICK; EXAFS AB The quick-scanning extended X-ray absorption fine structure technique of X-ray absorption spectroscopy has been employed to monitor structural changes during the cyclic electrochemical oxidation and reduction of nickel oxide thin film electrodes. The films were prepared by anodic deposition onto a graphite substrate at 1.1 V vs. SCE from a solution of 0.05 M NiSO4 + 0.5 CH3COONa. The freshly "as-deposited" film contained mainly Ni2+ and Ni4+ with highly disordered structures. The phase containing Ni2+ can be charged in 1 M of KOH solution to a phase containing Ni4+. Electrochemical reduction of a charged nickel oxide film at constant current leads to the formation of a Ni(OH), which transforms to P-Ni(OH), with time in the KOH solution. The discharged film can be recharged to form a phase which contains mostly Ni4+. The fraction of Ni4+ in the film increased with charging time and reached a value of 0.8 (i.e., 80% of Ni is present as Ni4+) after 38 min of charging at a constant current of 1.68 mA/cm(2). The Ni4+ phase is structurally similar to that of a NiO2 phase produced by electrochemical oxidation of LiNiO2 in a nonaqueous electrolyte as has been shown previously. C1 USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. Argonne Natl Lab, Div Sci Mat, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Mansour, AN (reprint author), USN, Ctr Surface Warfare, Carderock Div, W Bethesda, MD 20817 USA. NR 29 TC 11 Z9 11 U1 1 U2 8 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1121 EP 1125 DI 10.1149/1.1838426 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900016 ER PT J AU Kong, FP Kostecki, R McLarnon, F AF Kong, FP Kostecki, R McLarnon, F TI In situ ellipsometric study of the electroprecipitation of nickel hydroxide films SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article; Proceedings Paper CT Meeting of the Electrochemical-Society CY MAY 04-09, 1997 CL MONTREAL, CANADA SP Electrochem Soc ID ATOMIC-FORCE MICROSCOPY; DIFFUSION-COEFFICIENT; PROTON DIFFUSION; DEPOSITION; BETA-NI(OH)(2) AB Ellipsometry was used to study the electroprecipitation of Ni(OH)(2) films onto mirror-finished Pt or Ni electrodes from 0.1 M Ni(NO3)(2) solution at current densities of -0.075, -0.15, -0.30, and -0.60 mA/cm(2). An automatic self-compensating ellipsometer was used to monitor in situ the as-deposited Ni(OH)(2) film properties until a charge density of 380 mC/cm(2) was passed. Plots of the measured ellipsometric parameters Delta and Psi vs. precipitation charge density revealed differences in the nature of the four films as well as the kinetics of the deposition process. The initial stage of Ni(OH)(2) deposition (up to 100 mC/cm(2)) at all current densities produced films with very similar optical and electrochemical properties. However, pronounced differences in the optical properties of the films appeared at longer precipitation times, with the films becoming less compact. Numerical analyses of the ellipsometric data provided evidence in support of a two-step electroprecipitation process, and indicated that the densities of freshly precipitated Ni(OH)(2) films fall in the range 1.25-1.50 g/cm(3), depending on the magnitude of the applied current density. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. RP Kong, FP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Environm Energy Technol Div, Berkeley, CA 94720 USA. NR 18 TC 9 Z9 9 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1174 EP 1178 DI 10.1149/1.1838434 PG 5 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900024 ER PT J AU Windisch, CF Virden, JW Elder, SH Liu, J Engelhard, MH AF Windisch, CF Virden, JW Elder, SH Liu, J Engelhard, MH TI Electrochemistry of TiN in 6 M KOH solution SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID RAMAN-SCATTERING; TITANIUM-DIOXIDE; TRANSITION; CORROSION; BEHAVIOR; EXCHANGE; SPECTRA; FILMS AB Cyclic polarization of TiN electrodes in 6 M KOH at room temperature revealed relatively large anodic and cathodic overpotentials for water decomposition that depend on the surface structure of the material. Polished TiN electrodes also underwent a slow reaction during anodic polarization above the reversible potential for O-2 evolution that involved the formation of a reaction product film. The film was uniform over the surface of the electrodes and contained hydrous potassium titanate. A corrosion product, similar in composition but less uniform in appearance, formed on TiN after 4 months under open-circuit conditions in the same solution. Results indicate that the film forms slowly by a dissolution/precipitation mechanism and that the dissolution step gives rise to an oxidation peak observed in the cyclic voltammogram during anodic polarization. Since the film forms above the reversible potential for O-2 evolution and since the overvoltage for O-2 evolution depends on surface structure, it is not yet clear whether the formation of the corrosion film will compete with electrolysis reactions during the charging of structurally tailored, high surface area, TiN electrodes that are under development for ultracapacitor applications. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Windisch, CF (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. RI Engelhard, Mark/F-1317-2010; OI Engelhard, Mark/0000-0002-5543-0812 NR 23 TC 20 Z9 20 U1 0 U2 4 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1211 EP 1218 DI 10.1149/1.1838441 PG 8 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900031 ER PT J AU Ein-Eli, Y Howard, WF Lu, SH Mukerjee, S McBreen, J Vaughey, JT Thackeray, MM AF Ein-Eli, Y Howard, WF Lu, SH Mukerjee, S McBreen, J Vaughey, JT Thackeray, MM TI LiMn2-xCuxO4 spinels (0.1 <= x <= 0.5): A new class of 5 V cathode materials for Li batteries - I. Electrochemical, structural, and spectroscopic studies SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID LITHIUM BATTERIES; VOLTAGE; CELLS AB A series of electroactive spinel compounds, LiMn2-xCuxO4 (0.1 less than or equal to x less than or equal to 0.5), has been studied by crystallographic, spectroscopic, and electrochemical methods and by electron microscopy. These LiMn2-xCuxO4, spinels are nearly identical in structure to cubic LiMn2O4 and successfully undergo reversible Li intercalation. The electrochemical data show a remarkable reversible electrochemical process at 4.9 V which is attributed to the oxidation of Cu2+ to Cu3+. The inclusion of Cu in the spinel structure enhances the electrochemical stability of these materials upon cycling. The initial capacity of LiMn2-xCuxO4 spinels decreases with increasing x from 130 mAh/g in LiMn2O4 (x=0) to 70 mAh/g in "LiMn1.5Cu0.5O4" (x=0.5). The data also show slight shifts to higher voltage for the delithiation reaction that normally occurs at 4.1 V in standard Li1-xMn2O4 electrodes (1 greater than or equal to x greater than or equal to 0) corresponding to the oxidation of Mn3+ to Mn4+. Although the powder X-ray diffraction pattern of "LiMn1.5Cu0.5O4" shows a single-phase spinel product, neutron diffraction data show a small but significant quantity of an impurity phase, the composition and structure of which could not be identified. X-ray absorption spectroscopy was used to gather information about the oxidation states of the manganese and copper ions. The composition of the spinel component in the LiMn1.5Cu0.5O4 was determined from X-ray diffraction and X-ray absorption near-edge spectroscopy to be Li1.01Mn1.67Cu0.32O4, suggesting to a best approximation that the impurity in the sample was a lithium-copper-oxide phase. The substitution of manganese by copper enhances the reactivity of the spinel structure toward hydrogen: the compounds are more easily reduced at moderate temperature (similar to 200 degrees C) than LiMn2O4. C1 Covalent Associates Inc, Woburn, MA 01801 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Argonne Natl Lab, Argonne, IL 60439 USA. RP Ein-Eli, Y (reprint author), Covalent Associates Inc, Woburn, MA 01801 USA. RI Ein-Eli, Yair/F-1370-2011; OI Vaughey, John/0000-0002-2556-6129 NR 26 TC 148 Z9 153 U1 1 U2 33 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1238 EP 1244 DI 10.1149/1.1838445 PG 7 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900035 ER PT J AU Griffiths, SK Nilson, RH AF Griffiths, SK Nilson, RH TI Optimum conditions for composites fiber coating by chemical vapor infiltration SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article AB A combined analytical and numerical method is employed to optimize process conditions for composites fiber coating by chemical vapor infiltration. For a first-order deposition reaction, the optimum pressure yielding the maximum deposition rate at a preform center is obtained in closed form and is :found to depend only on the activation energy of the deposition reaction, the characteristic pore size, and properties of the reactant and product gases. It does not depend on the preform specific surface area, effective diffusivity or preform thickness, nor on the gas-phase yield of the deposition reaction. Further, this optimum pressure is unaltered by the additional constraint of a prescribed deposition uniformity Optimum temperatures are obtained using an analytical expression for the optimum value along with numerical solutions to the governing transport equations. These solutions account for both diffusive and advective transport, as well as both ordinary and Knudsen diffusion. Sample calculations are presented for coating preform fibers with boron nitride. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Griffiths, SK (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 20 TC 7 Z9 8 U1 0 U2 1 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1263 EP 1272 DI 10.1149/1.1838449 PG 10 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900039 ER PT J AU McHugo, SA Weber, ER Myers, SM Petersen, GA AF McHugo, SA Weber, ER Myers, SM Petersen, GA TI Gettering of iron to implantation induced cavities and oxygen precipitates in silicon SO JOURNAL OF THE ELECTROCHEMICAL SOCIETY LA English DT Article ID CZOCHRALSKI SILICON; TRANSITION-METALS; DIFFUSION LENGTH; PHOSPHORUS; COPPER; GOLD; IMPURITIES; ALUMINUM; COBALT; CARBON AB Iron gettering at both implantation-induced cavities and oxygen precipitates in silicon was experimentally measured and theoretically modeled. Since impurity removal from the near-surface region is crucial for proper integrated circuit device operation, these experiments strictly tested the viability of each mechanism to sufficiently reduce the near-surface Fe concentration. Cavities and oxygen precipitates were formed by helium implantation in the near surface region and specific heat treatments, respectively. Low doses of intentionally introduced Fe were gettered with either a short rapid thermal anneal or a long furnace anneal, both at moderate temperatures. The Fe concentration was measured in the near surface region as well as in the cavities. The cavities were found to drastically reduce near-surface Fe concentrations for both anneals while the oxygen precipitates were only fairly effective for long furnace anneals. Furthermore, for samples with both cavities and oxygen precipitates, the gettering of Fe was only slightly enhanced over samples with only cavities. The experimental results were supported by a semiquantitative agreement with modeling based on previously derived theoretical formalisms. These experimental results clearly show an increased gettering effectiveness of implantation-induced cavities over oxygen precipitates for impurity removal from the near-surface region. C1 Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP McHugo, SA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 38 TC 18 Z9 18 U1 0 U2 2 PU ELECTROCHEMICAL SOC INC PI PENNINGTON PA 10 SOUTH MAIN STREET, PENNINGTON, NJ 08534 USA SN 0013-4651 J9 J ELECTROCHEM SOC JI J. Electrochem. Soc. PD APR PY 1998 VL 145 IS 4 BP 1400 EP 1405 DI 10.1149/1.1838472 PG 6 WC Electrochemistry; Materials Science, Coatings & Films SC Electrochemistry; Materials Science GA ZD712 UT WOS:000072715900062 ER PT J AU Pride, SR Berryman, JG AF Pride, SR Berryman, JG TI Connecting theory to experiment in poroelasticity SO JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS LA English DT Article DE constitutive behaviour; granular material; porous material; geological material; volume averaging ID POROUS-MEDIA; EQUATIONS; FLUID; ROCK; COMPRESSIBILITY; CONSTITUENTS AB The variables controlled and measured in elastostatic laboratory experiments (the volume changes, shape changes, confining stresses, and pore pressure) are exactly related to the appropriate variables of poroelastic field theory (the gradients of the volume-averaged displacement fields and the volume averaged stresses). The relations between the laboratory and volume-averaged strain measures require the introduction of a new porous-material geometrical term. In the anisotropic case, this term is a tensor that is related both to the presence of porosity gradients and to a type of weighted surface porosity. In the isotropic case, the term reduces to a scalar and depends only on the surface-porosity parameter. When this surface-porosity parameter is identical to the usual volume porosity, the relations initially proposed by Blot and Willis are recovered. The exact statement of the poroelastic strain-energy density is derived and is used to define both the laboratory strain measures and the laboratory elastic moduli. Only two restrictions are placed on the materials bring treated: (1) the fluid is homogeneous in each sample and (2) the material possesses a rigidity. However, the entire work is limited to linear deformations and long (relative to sample size) wavelengths of applied stress. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Inst Phys Globe, Dept Geomagnetisme, F-75252 Paris 05, France. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Univ Rennes 1, Batiment 15, F-35042 Rennes, France. RI Berryman, James/A-9712-2008 NR 29 TC 39 Z9 39 U1 1 U2 6 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0022-5096 EI 1873-4782 J9 J MECH PHYS SOLIDS JI J. Mech. Phys. Solids PD APR PY 1998 VL 46 IS 4 BP 719 EP 747 DI 10.1016/S0022-5096(97)00043-4 PG 29 WC Materials Science, Multidisciplinary; Mechanics; Physics, Condensed Matter SC Materials Science; Mechanics; Physics GA ZK590 UT WOS:000073340400006 ER PT J AU Kaushik, S AF Kaushik, S TI Vector Fresnel equations and Airy formula for one-dimensional multilayer and surface-relief gratings: reply to comment SO JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION LA English DT Article ID DIFFRACTION GRATINGS; MATRIX AB In a recent paper [J. Opt. Soc, Am. A 14, 596 (1997)], S. Kaushik describes a modal theory of diffraction in which a number of features from scalar optics are generalized. The paper describes an S-matrix propagation algorithm that is characterized as being new and an improvement over earlier work. In a response to this paper, L. Li [J. Opt. Soc. Am. A. 15, 1006 (1998)] disputes this claim and claims that the algorithm is well known and presents no significant improvement over earlier work. These criticisms are addressed in this reply. Specifically, it is shown that unlike earlier work cited by Li, the method described by Kaushik is a genuine S-matrix method since energy balance is automatically guaranteed for dielectric gratings, irrespective of truncation order. Further, it is shown that the algorithm is easier to relate to scalar optics and is computationally more efficient than the specific algorithms cited by Li. (C) 1998 Optical Society of America. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Kaushik, S (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 17 TC 0 Z9 0 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0740-3232 J9 J OPT SOC AM A JI J. Opt. Soc. Am. A-Opt. Image Sci. Vis. PD APR PY 1998 VL 15 IS 4 BP 1009 EP 1011 DI 10.1364/JOSAA.15.001009 PG 3 WC Optics SC Optics GA ZD744 UT WOS:000072719100024 ER PT J AU Keating, GN Valentine, GA AF Keating, GN Valentine, GA TI Proximal stratigraphy and syn-eruptive faulting in rhyolitic Grants Ridge Tuff, New Mexico, USA SO JOURNAL OF VOLCANOLOGY AND GEOTHERMAL RESEARCH LA English DT Article DE volcanic deposits; rhyolite; Grants Ridge Tuff; syn-eruptive faulting; proximal stratigraphy ID IGNIMBRITE; VALLEY AB Proximal deposits of the 3.3 Ma Grants Ridge Tuff, part of a 5-km(3) topaz rhyolite sequence, are composed of basal pyroclastic flow, surge, and fallout deposits, a thick central ignimbrite, and upper surge and fallout deposits. Large lithic blocks (less than or equal to 2 m) of underlying sedimentary and granitic bedrock that are present in lower pyroclastic flow and fallout deposits indicate that the eruptive sequence began with explosive, conduit-excavating eruptions. The massive, nonwelded central ignimbrite displays evidence for postemplacement deformation. The upper pyroclastic surge deposits are dominated by fine ash, some beds containing accretionary lapilli, soft-sediment deformation features, and mud-coated Lithic lapilli, indicating an explosive, hydromagmatic component to these later eruptions. The upper fall and surge deposits are overlain by fluvially reworked volcaniclastic deposits that truncate the primary section with a relatively planar surface. The proximal, upper pyroclastic surge and Plinian fall deposits are preserved only in small grabens (5-8 m deep and wide), where they subsided into the ignimbrite and were protected from reworking. The pyroclastic surge and fall deposits within the grabens are offset by numerous small normal faults. The offset on some faults decreases upward through the section, indicating that the faulting process may have been syn-eruptive. Several graben-bounding faults extend downward into the ignimbrite, but the uppermost, fluvially reworked tephra layers are not cut by these faults. The faulting mechanism may have been related to settling and compaction of the 60 m thick, valley-filling ignimbrite along the axis of the paleovalley. Draping surge contacts against the graben faults and brittle and soft-style disruption of the upper pyroclastic surge beds indicate that subsidence was ongoing during the emplacement of the upper eruptive sequence. Seismicity accompanying the late-stage hydromagmatic explosions may have contributed to the abrupt settling and compaction of the ignimbrite. (C) 1998 Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Geoanal Grp, Los Alamos, NM 87545 USA. RP Keating, GN (reprint author), Univ Calif Los Alamos Natl Lab, Geoanal Grp, Mail Stop F665, Los Alamos, NM 87545 USA. NR 19 TC 7 Z9 7 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0377-0273 J9 J VOLCANOL GEOTH RES JI J. Volcanol. Geotherm. Res. PD APR PY 1998 VL 81 IS 1-2 BP 37 EP 49 DI 10.1016/S0377-0273(97)00075-9 PG 13 WC Geosciences, Multidisciplinary SC Geology GA ZP053 UT WOS:000073711800003 ER PT J AU Kennamer, RA Brisbin, IL McCreedy, CD Burger, J AF Kennamer, RA Brisbin, IL McCreedy, CD Burger, J TI Radiocesium in mourning doves: Effects of a contaminated reservoir drawdown and risk to human consumers SO JOURNAL OF WILDLIFE MANAGEMENT LA English DT Article DE contaminant; Cs-137; drawdown; human risk; mourning dove; radiocesium; reservoir; South Carolina; Zenaida macroura ID RADIONUCLIDE CONCENTRATIONS; PATTERNS; REACTOR; CS-137; EGGS AB From September 1991 through January 1995, partial drawdown of a 1,130-ha U.S. Department of Energy reactor cooling reservoir (Par Pond) in South Carolina exposed sediments contaminated by low-level radiocesium (Cs-137). These exposed sediments were designated as a U.S. Environmental Protection Agency (EPA) superfund site, Whole-body and muscle concentrations of Cs-137 in mourning doves (Zenaida macroura) collected from Par Pond in 1992 and 1993 were 2-3 orders of magnitude higher than in doves from nearby public dove-hunting fields located 12 and 32 km away Only 1 of 102 Par Pond doves exceeded the European Economic Community limit of 0.60 Becquerels (Bq)Cs-137/g for fresh meat. A human risk analysis based on consumption of doves at the observed maximum of muscle Cs-137 concentration (0.82 Bq/g wet mass) indicated no more than 41 doves could be consumed by an individual per lear at that level before the EPA threshold for action on a superfund site would be exceeded (i.e., further site characterization, possible remedial action). Levels of whole-body Cs-137 in doves from Par Pond declined by >75% from 1992 through 1994. Pokeweed (Phytolacca americana) seeds, the dominant food of doves foraging on the exposed lake bed, likewise declined (>90%) in Cs-137 content over the period. We noted subtle annual changes in the diets of doves that likely contributed to reduced rates of Cs-137 ingestion as the drawdown progressed. Doves differed by age class in their food intake and selection, and immature doves showed higher levels of ingesta Cs-137. However, age classes did not differ in whole-body Cs-137 (P = 0.156) or muscle Cs-137 (P = 0.181). Dove whole-body Cs-137 was a good predictor (r(2) = 0.94) of muscle Cs-137, and thus provides the opportunity to estimate levels of Cs-137 in edible muscle without destructive sampling by simply subjecting live-captured birds to whole-bod. determination of Cs-137 content. The radiological consequences of a long-term drawdown or complete draining of such a reservoir are not clear. C1 Savannah River Ecol Lab, Aiken, SC 29802 USA. Purdue Univ, Dept Vet Pathobiol, W Lafayette, IN 47907 USA. Rutgers State Univ, Nelson Biol Labs, Piscataway, NJ 08855 USA. Rutgers State Univ, Environm & Occupat Hlth Sci Inst, Piscataway, NJ 08855 USA. RP Kennamer, RA (reprint author), Savannah River Ecol Lab, PO Drawer E, Aiken, SC 29802 USA. EM kennamer@srel.edu NR 39 TC 8 Z9 9 U1 2 U2 4 PU WILDLIFE SOC PI BETHESDA PA 5410 GROSVENOR LANE, BETHESDA, MD 20814-2197 USA SN 0022-541X J9 J WILDLIFE MANAGE JI J. Wildl. Manage. PD APR PY 1998 VL 62 IS 2 BP 497 EP 508 DI 10.2307/3802323 PG 12 WC Ecology; Zoology SC Environmental Sciences & Ecology; Zoology GA ZJ057 UT WOS:000073175200006 ER PT J AU Stork, CHJ Butterfield, CP Holley, W Madsen, PH Jensen, PH AF Stork, CHJ Butterfield, CP Holley, W Madsen, PH Jensen, PH TI Wind conditions for wind turbine design proposals for revision of the IEC 1400-1 standard SO JOURNAL OF WIND ENGINEERING AND INDUSTRIAL AERODYNAMICS LA English DT Article; Proceedings Paper CT 2nd European and African Conference on Wind Engineering CY JUN 22-26, 1997 CL GENOA, ITALY SP Univ Genova, Dept Struct & Geotech Engn, Int Assoc Wind Engn, Italian Natl Assoc Wind Engn, Liguria Reg, Province Genova, Municipal Genova, UNESCO DE wind turbine; IEC 1400-1; safety requirements; wind conditions; turbulence; gust; wind shear; wind direction change AB The International Electrotechnical Commission (IEC) TC88 formed a subcommittee to re-evaluate the external wind condition models defined in the standard for "Wind Turbine Generator Systems, Part I: Safety Requirements" 1400-1. These models define design turbulence conditions, extreme gust transients, extreme wind direction transients and extreme shear transients as well as other normal and extreme conditions. The TC88 subcommittee solicited extreme wind condition data from countries throughout the world reporting such parameters as maximum gust magnitudes, minimum gust rise times, and extreme wind shears. These data were used to modify the IEC models to be more representative of typical field conditions. Some data used for comparison together with the new models are presented. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Riva Calzoni, I-40033 Bologna, Italy. Natl Renewable Energy Lab, Golden, CO USA. Riso Natl Lab, DK-4000 Roskilde, Denmark. RP Stork, CHJ (reprint author), Riva Calzoni, Via E Ponente 72, I-40033 Bologna, Italy. NR 1 TC 8 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-6105 J9 J WIND ENG IND AEROD JI J. Wind Eng. Ind. Aerodyn. PD APR-AUG PY 1998 VL 74-6 BP 443 EP 454 DI 10.1016/S0167-6105(98)00040-3 PG 12 WC Engineering, Civil; Mechanics SC Engineering; Mechanics GA 110LR UT WOS:000075383400038 ER PT J AU Pais, P Knize, MG AF Pais, P Knize, MG TI Photodiode-array HPLC peak matching for complex thermally processed samples SO LC GC-MAGAZINE OF SEPARATION SCIENCE LA English DT Article ID HETEROCYCLIC AROMATIC-AMINES; PERFORMANCE LIQUID-CHROMATOGRAPHY; ELECTROCHEMICAL DETECTION; FOOD-PRODUCTS; BEEF EXTRACTS; COOKED FOOD; MUTAGENS; QUANTIFICATION; CARCINOGENS; FLAVORS C1 Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, Livermore, CA 94551 USA. RP Knize, MG (reprint author), Univ Calif Lawrence Livermore Natl Lab, Mol & Struct Biol Div, Biol & Biotechnol Res Program, L-452,POB 808, Livermore, CA 94551 USA. NR 21 TC 6 Z9 7 U1 0 U2 0 PU ADVANSTAR COMMUNICATIONS PI DULUTH PA 131 W FIRST ST, DULUTH, MN 55802 USA SN 0888-9090 J9 LC GC-MAG SEP SCI JI LC GC-Mag. Sep. Sci. PD APR PY 1998 VL 16 IS 4 BP 378 EP + PG 4 WC Chemistry, Analytical SC Chemistry GA ZJ435 UT WOS:000073215400006 ER PT J AU Schepkin, VD Choy, IO Budinger, TF Obayashi, DY Taylor, SE DeCampli, WM Amartur, SC Young, JN AF Schepkin, VD Choy, IO Budinger, TF Obayashi, DY Taylor, SE DeCampli, WM Amartur, SC Young, JN TI Sodium TQF NMR and intracellular sodium in isolated crystalloid perfused rat heart SO MAGNETIC RESONANCE IN MEDICINE LA English DT Article DE intracellular sodium; triple quantum filter; calcium paradox; ischemia ID NUCLEAR-MAGNETIC-RESONANCE; FILTERED NA-23 NMR; CARDIAC PURKINJE-FIBERS; FERRET VENTRICULAR MUSCLE; CALCIUM PARADOX; CELLULAR-ENERGY; ISCHEMIA; NA+; EXCHANGE; QUANTIFICATION AB The feasibility of monitoring intracellular sodium changes using Na triple quantum filtered NMR without a chemical shift reagent (SR) was investigated in an isolated rat heart during a variety of interventions for Na, loading. Perfusion with 1 mM ouabain or without K+ present in the perfusate for 30 min produced a rise of the Na TQF signal with a plateau of similar to 190% and similar to 228% relative to the preintervention level, respectively. Stop-flow ischemia for 30 min resulted in a TQF signal growth of similar to 147%. The maximal Na TQF signal increase of 460% was achieved by perfusion without K+/Ca2+, corresponding to an elimination of the Na transmembrane gradient. The observed values of Na NMR TQF growth in the physiological and pathological ranges are in agreement with reported data by other methods and have a linear correlation with intracellular sodium content as determined in this study by Co-EDTA method and by sucrose-histidine washout of the extracellular space. Our data indicate that the increase in Na TQF NMR signal is determined by the growth of Na-i, and the extracellular Na contribution to the total TQF signal is unchanged at similar to 64%. In conclusion, Na TQF NMR without using SR offers a unique and noninvasive opportunity to monitor alterations of intracellular sodium. It may provide valuable insights for developing cardioprotective strategies and for observing the effects of pharmaceutical treatments on sodium homeostasis. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Childrens Hosp Oakland, Div Cardiothorac Surg, Oakland, CA USA. RP Budinger, TF (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, 1 Cyclotron Rd,MS 55-121, Berkeley, CA 94720 USA. RI Schepkin, Victor/A-1245-2007 NR 49 TC 18 Z9 18 U1 0 U2 3 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0740-3194 J9 MAGNET RESON MED JI Magn.Reson.Med. PD APR PY 1998 VL 39 IS 4 BP 557 EP 563 DI 10.1002/mrm.1910390408 PG 7 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZD581 UT WOS:000072700900007 PM 9543417 ER PT J AU Geisler, JG Stubbs, LJ Wasserman, WW Mucenski, ML AF Geisler, JG Stubbs, LJ Wasserman, WW Mucenski, ML TI Molecular cloning of a novel mouse gene with predominant muscle and neural expression SO MAMMALIAN GENOME LA English DT Article ID MUSCULAR-DYSTROPHY GENE; RNA POLYMERASE-II; TRANSCRIPTIONAL ENHANCER; REGULATORY ELEMENTS; PROMOTER SEQUENCES; PROTEIN; BRAIN; BINDING; SKELETAL; CELLS AB Because numerous diseases affect the muscle and nervous systems, it is important to identify and characterize genes that may play functional roles in these tissues. Sequence analysis of a 106-kb region of human Chromosome (Chr) 19q13.2 revealed a novel gene with homology to the Neuroendocrine-specific protein (NSP), and it has, therefore, been designated NSP-like 1 (Nspl1). We isolated the mouse homolog of this gene and performed extensive expression analysis of both the mouse and human genes. The mouse Nspl1 gene is alternatively spliced to produce two major transcripts: a 2.1-kb mRNA that is expressed at highest levels in the brain, and a 1.2-kb transcript that is primarily expressed in muscle. The larger message contains 10 exons, whereas the smaller transcript contains 7 exons. The last 6 exons, which are present in both transcripts, share significant amino acid sequence identity with the endoplasmic reticulum-bound portion of NSP. Mouse and human Nspl1/NSPL1 genes have expression patterns that are similar to that of the dystrophin gene. In addition, the putative regulatory domains of Nspl1 appear similar in composition and distribution to the defined dystrophin regulatory sequences. C1 Univ Tennessee, Grad Sch Biomed Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. SmithKline Beecham Pharmaceut, Res & Dev, Bioinformat Grp, King Of Prussia, PA 19406 USA. RP Geisler, JG (reprint author), Univ Tennessee, Grad Sch Biomed Sci, POB 2009, Oak Ridge, TN 37831 USA. RI Wasserman, Wyeth/I-4866-2015; OI Stubbs, Lisa/0000-0002-9556-1972 NR 50 TC 25 Z9 27 U1 0 U2 0 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0938-8990 J9 MAMM GENOME JI Mamm. Genome PD APR PY 1998 VL 9 IS 4 BP 274 EP 282 PG 9 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Genetics & Heredity GA ZC877 UT WOS:000072628000002 PM 9530622 ER PT J AU Gladysz, GM Schmucker, M Chawla, KK Schneider, H Joslin, DL Ferber, MK AF Gladysz, GM Schmucker, M Chawla, KK Schneider, H Joslin, DL Ferber, MK TI Characterization of the reaction products that develop in the processing of Al2O3/BaZrO3 laminated composites SO MATERIALS CHARACTERIZATION LA English DT Article ID ALUMINA; INTERFACE; MONAZITE AB The absence of a chemical reaction at an interface is conventionally thought to be an important criterion in producing a tough ceramic matrix composite (CMC). As a result of this criterion, interphases in CMCs were chosen on the basis of their chemical reactivity. A weak interface results in crack deflection, crack bridging, and, in fiber-reinforced ceramics, fiber pullout, resulting in an increased fracture toughness. In this paper, we present microstructural observations on alumina (Al2O3)-barium zirconate (BaZrO3) laminated composites wherein the reaction products that develop during processing resulted in sharp interfaces and appear to be weak enough to deflect cracks. These in situ reaction products in Al2O3-BaZrO3 laminated composites were characterized with the use of a scanning electron microscope, an electron microprobe, and a transmission electron microscope. The phases that develop, ZrO2, BaO . Al2O3, and BaO . 6 Al2O3, produced sharp interfaces and are arranged in a sequence that could be predicted by using information from the phase diagram. (C) Elsevier Science inc., 1998. C1 Youngstown State Univ, Dept Chem, Youngstown, OH 44555 USA. German Aerosp Estab DLR, Inst Mat Res, D-51140 Cologne, Germany. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Alabama, Dept Mech & Mat Engn, Birmingham, AL 35294 USA. RP Gladysz, GM (reprint author), Youngstown State Univ, Dept Chem, Youngstown, OH 44555 USA. NR 6 TC 11 Z9 11 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 1044-5803 J9 MATER CHARACT JI Mater. Charact. PD APR-JUN PY 1998 VL 40 IS 4-5 BP 209 EP 214 DI 10.1016/S1044-5803(98)00011-4 PG 6 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Materials Science, Characterization & Testing SC Materials Science; Metallurgy & Metallurgical Engineering GA 106CX UT WOS:000075113100002 ER PT J AU Bailey, J AF Bailey, J TI Laser Ablation Laser Induced Fluorescence SO MEASUREMENTS & CONTROL LA English DT Article AB Pacific Northwest National Laboratory (PNNL) is completing the principle research and development of an instrument that will assay samples of uranium metal debris and return the percent by weight of two of the constituent isotopes within a few hours. The instrument can be hand-carried in the field and can be transported on commercial airlines. The instrument is to be used by the International Atomic Energy field investigators to verify compliance with international national nuclear treaties. C1 Pacific NW Lab, Richland, WA 99352 USA. RP Bailey, J (reprint author), Pacific NW Lab, POB 999, Richland, WA 99352 USA. NR 0 TC 0 Z9 0 U1 1 U2 1 PU MEASUREMENTS & DATA CORP PI PITTSBURGH PA 2994 W LIBERTY AVE, PITTSBURGH, PA 15216 USA SN 0148-0057 J9 MEAS CONTROL-US JI Meas. Control PD APR PY 1998 IS 188 BP 116 EP 119 PG 4 WC Automation & Control Systems; Instruments & Instrumentation SC Automation & Control Systems; Instruments & Instrumentation GA ZK192 UT WOS:000073294600005 ER PT J AU Verhoeven, JD Gibson, ED AF Verhoeven, JD Gibson, ED TI The divorced eutectoid transformation in steel SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID ULTRAHIGH CARBON-STEELS; PEARLITE; AUSTENITE AB Experiments are presented which show that the eutectoid transformation in steel can occur by two different modes for temperatures just slightly below A(1). In the normal mode, the transformation product is lamellar pearlite. The second mode occurs if the austenite contains cementite particles or nuclei with a spacing on the order of a few microns or less. In this case, the transformation product consists of spheroidal cementite particles in a ferrite matrix. This second mode is here called the divorced eutectoid transformation (DET), after recent work by Sherby and co-workers. A literature survey shows that the faster kinetics of the DET over lamellar pearlite in the presence of inhomogeneous austenite was established before 1940, but has received little attention. The inhomogeneities are generally small cementite particles. Experiments show that the DET does not occur by a shell of one phase (ferrite) forming around the other phase of the eutectoid (cementite), as is the case in divorced eutectic growth. Rather, a fairly planar austenite/ferrite front simply advances into the austenite, with no apparent effect on its shape being produced by the cementite particles. A first-order kinetic model is presented for the growth velocity as a function of undercooling below A(1) and is compared to the velocity vs undercooling for lamellar pearlite. The simple model indicates that the velocity of the divorced mode should be faster than the lamellar mode at low undercooling for cementite nuclei distributed in the austenite with spacings less than a few microns. This result is consistent with the experimental data. C1 Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. Iowa State Univ Sci & Technol, Ames Lab, Ames, IA 50011 USA. RP Verhoeven, JD (reprint author), Iowa State Univ Sci & Technol, Dept Mat Sci & Engn, Ames, IA 50011 USA. NR 46 TC 49 Z9 55 U1 1 U2 9 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD APR PY 1998 VL 29 IS 4 BP 1181 EP 1189 DI 10.1007/s11661-998-0245-4 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZK623 UT WOS:000073343700006 ER PT J AU Mitlin, D German, RM AF Mitlin, D German, RM TI An examination of the interparticle contact area during sintering of W-0.3 Wt pct Co SO METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE LA English DT Article ID MODEL AB As a powder compact sinters, its microstructure evolves. One way to quantify the scale of the microstructure is to consider the interparticle contact area. This study examines two known models for calculating the interparticle contact area: the classic two-sphere model and the Voronoi cell model. Both models have particular assumptions about the microstructure that make them not applicable for treating densification to near full density with concurrent grain growth. The classic two-sphere model assumes a regular packing of particles and a perfectly spherical particle geometry and neglects an increasing particle coordination number with sintering. The Voronoi cell model assumes that the scale of the microstructure remains constant; i.e., as long as the compact is densifying, grain growth does not occur. We propose a modified Voronoi cell that accounts for an increasing grain size, making it applicable to a general case where grain growth occurs during sintering. The three models are compared to the interparticle contact area data, obtained by stereology techniques, for W-0.3 wt pet Co sinterrd from green state to near full density. The original Voronoi cell model fits the data only at low temperatures, before the onset of grain growth. Below approximately 90 pet relative density, the two-sphere model with an assumed coordination number of six (coordination number in a green compact) and the modified Voronoi cell model provide a good fit to the data. At higher densities, both models overestimate the interparticle contact area. C1 Penn State Univ, Dept Engn Sci & Mech, PM Lab, University Pk, PA 16802 USA. RP Mitlin, D (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Adv Mat, Berkeley, CA 94720 USA. RI Mitlin , David /M-5328-2016; OI Mitlin , David /0000-0002-7556-3575; German, Randall/0000-0002-5676-8532 NR 28 TC 4 Z9 4 U1 1 U2 2 PU MINERALS METALS MATERIALS SOC PI WARRENDALE PA 420 COMMONWEALTH DR, WARRENDALE, PA 15086 USA SN 1073-5623 J9 METALL MATER TRANS A JI Metall. Mater. Trans. A-Phys. Metall. Mater. Sci. PD APR PY 1998 VL 29 IS 4 BP 1309 EP 1317 DI 10.1007/s11661-998-0257-0 PG 9 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZK623 UT WOS:000073343700018 ER PT J AU Cohen, A Blander, M AF Cohen, A Blander, M TI Removal of copper from carbon-saturated iron with an aluminum sulfide ferrous sulfide flux SO METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE LA English DT Article ID MELT C1 Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem Technol, Argonne, IL 60439 USA. RP Cohen, A (reprint author), Argonne Natl Lab, Div Energy Technol, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 12 TC 3 Z9 3 U1 1 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1073-5615 J9 METALL MATER TRANS B JI Metall. Mater. Trans. B-Proc. Metall. Mater. Proc. Sci. PD APR PY 1998 VL 29 IS 2 BP 493 EP 495 DI 10.1007/s11663-998-0129-4 PG 3 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZJ613 UT WOS:000073234300023 ER PT J AU Tobin, KW Gleason, SS Karnowski, TP Guidry, D AF Tobin, KW Gleason, SS Karnowski, TP Guidry, D TI Using SSA to measure the efficacy of automated defect data gathering SO MICRO LA English DT Article C1 Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. Knights Technol Div Electroglas, Sunnyvale, CA USA. RP Tobin, KW (reprint author), Oak Ridge Natl Lab, Image Sci & Machine Vis Grp, Oak Ridge, TN 37831 USA. NR 5 TC 3 Z9 3 U1 0 U2 0 PU CANON COMMUNICATIONS INC PI SANTA MONICA PA 3340 OCEAN PARK BLVD, SUITE 1000, SANTA MONICA, CA 90405 USA SN 1081-0595 J9 MICRO JI Micro PD APR PY 1998 VL 16 IS 4 BP 27 EP 33 PG 7 WC Engineering, Electrical & Electronic; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Condensed Matter SC Engineering; Science & Technology - Other Topics; Materials Science; Physics GA 147ZL UT WOS:000077527700025 ER PT J AU Hunt, EM Wang, ZL Evans, ND Hampikian, JM AF Hunt, EM Wang, ZL Evans, ND Hampikian, JM TI High-spatial resolution compositionally-sensitive imaging of metallic particles using plasmon energy-loss electrons in TEM SO MICRON LA English DT Review DE energy-filtering; aluminum; alumina; plasmon; compositionally sensitive imaging; spatial resolution ID SURFACES AB High spatial resolution elemental maps have been demonstrated in studies of Y+ implanted alumina and Al/Ti multilayer specimens using energy-filtered transmission electron microscopy. A spatial resolution of similar to 2 nm is achieved. Aluminum containing particles formed in Y+ implanted alumina have been identified using energy-filtered images formed with plasmon energy-loss electrons. Noncrystalline aluminum containing particles in specimens implanted at lower ion energies are also observed and the image contrast can be reasonably interpreted using a compositional shell model. Published by Elsevier Science Ltd. C1 Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. Oak Ridge Inst Sci & Educ, Oak Ridge, TN 37831 USA. RP Hampikian, JM (reprint author), Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. RI Evans, Neal/F-5955-2011; Wang, Zhong Lin/E-2176-2011 OI Wang, Zhong Lin/0000-0002-5530-0380 NR 17 TC 7 Z9 7 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0968-4328 J9 MICRON JI Micron PD APR-JUN PY 1998 VL 29 IS 2-3 BP 191 EP 199 DI 10.1016/S0968-4328(97)00056-5 PG 9 WC Microscopy SC Microscopy GA 102LJ UT WOS:000074925600011 ER PT J AU Tsiao, CJ Carrado, KA Botto, RE AF Tsiao, CJ Carrado, KA Botto, RE TI Investigation of the microporous structure of clays and pillared clays by Xe-129 NMR SO MICROPOROUS AND MESOPOROUS MATERIALS LA English DT Article DE clay structure; pillared clays; Xe-129 NMR; gallery height ID CHEMICAL-SHIFT; XENON; ZEOLITES; MONTMORILLONITE; SPECTROSCOPY; METAL AB Xe-129 NMR spectroscopy of xenon gas adsorbed in clays and pillared clays has been used to glean information on the interlayer gallery height of clays before and after pillaring. Two clay minerals were studied, a Ca2+-montmorillonite and Bentonite L. The NMR results indicate that the effective interlamellar spacing of the montmorillonite increased from 5.4 to 8.0 Angstrom after pillaring with aluminum polyoxohydroxy Keggin cations. These data are consistent with X-ray powder diffraction results, which show a corresponding increase in gallery height from 5.6 to 8.4 Angstrom. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Botto, RE (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 26 TC 12 Z9 14 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1387-1811 J9 MICROPOR MESOPOR MAT JI Microporous Mesoporous Mat. PD APR PY 1998 VL 21 IS 1-3 BP 45 EP 51 DI 10.1016/S1387-1811(97)00040-1 PG 7 WC Chemistry, Applied; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary SC Chemistry; Science & Technology - Other Topics; Materials Science GA 115RK UT WOS:000075678800007 ER PT J AU Hipwell, MC Tien, CL Mao, XL Russo, RE AF Hipwell, MC Tien, CL Mao, XL Russo, RE TI Picosecond differential transmission measurements on porous silicon SO MICROSCALE THERMOPHYSICAL ENGINEERING LA English DT Article ID NONLINEAR-TRANSMISSION; DYNAMICS; ELECTROLUMINESCENCE; NANOCRYSTALLITES; ABSORPTION; FILMS AB In this work, differential transmission measurements are made to characterize the short-time-scale optical properties of p-type light-emitting porous silicon. Aged and freshly etched samples are used to determine the impact of aging on the nonlinear optical properties. Two-component photo-induced absorption is observed in both types of samples. A model that considers porous silicon's unique properties of confinement, high surface area, and disorder on several length scales is presented to explain the experimental results. C1 Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA USA. RP Hipwell, MC (reprint author), Seagate Technol, 7801 Comp Ave S, Bloomington, MN 55435 USA. NR 22 TC 2 Z9 2 U1 4 U2 4 PU TAYLOR & FRANCIS INC PI PHILADELPHIA PA 325 CHESTNUT ST, SUITE 800, PHILADELPHIA, PA 19106 USA SN 1089-3954 J9 MICROSCALE THERM ENG JI Microscale Thermophys. Eng. PD APR-JUN PY 1998 VL 2 IS 2 BP 87 EP 99 PG 13 WC Thermodynamics; Engineering, Mechanical; Nanoscience & Nanotechnology; Materials Science, Characterization & Testing; Physics, Applied SC Thermodynamics; Engineering; Science & Technology - Other Topics; Materials Science; Physics GA ZU013 UT WOS:000074152500003 ER PT J AU Myers, CA Schmidhauser, C Mellentin-Michelotti, J Fragoso, G Roskelley, CD Casperson, G Mossi, R Pujuguet, P Hager, G Bissell, MJ AF Myers, CA Schmidhauser, C Mellentin-Michelotti, J Fragoso, G Roskelley, CD Casperson, G Mossi, R Pujuguet, P Hager, G Bissell, MJ TI Characterization of BCE-1, a transcriptional enhancer regulated by prolactin and extracellular matrix and modulated by the state of histone acetylation SO MOLECULAR AND CELLULAR BIOLOGY LA English DT Article ID BETA-CASEIN GENE; MAMMARY EPITHELIAL-CELLS; DNA-BINDING PROTEINS; FUNCTIONAL-DIFFERENTIATION; MAMMALIAN-CELLS; SIGNAL-TRANSDUCTION; CHROMATIN STRUCTURE; RESPONSE ELEMENT; SODIUM-BUTYRATE; GROWTH-FACTOR AB We have previously described a 160-bp enhancer (BCE-1) in the bovine beta-casein gene that is activated in the presence of prolactin and extracellular matrix (ECM). Here we report the characterization of the enhancer by deletion and site-directed mutagenesis, electrophoretic mobility shift analysis, and in vivo footprinting. Two essential regions were identified by analysis of mutant constructions: one binds C/EBP-beta and the other binds MGF/STAT5 and an as-yet-unidentified binding protein. However, no qualitative or quantitative differences in the binding of these proteins were observed in electrophoretic mobility shift analysis using nuclear extracts derived from cells cultured in the presence or absence of ECM with or without pro!actin, indicating that prolactin-and ECM-induced transcription was not dependent an the availability of these factors in the functional cell lines employed, An in vivo footprinting analysis of the factors bound to nuclear chromatin in the presence or absence of ECM and/or prolactin found no differences in the binding of C/EBP-beta but did not protide definitive results for the other factors, Neither ECM nor prolactin activated BCE-1. in transient transactions, suggesting that the chromosomal structure of the integrated template may he required for ECM-induced transcription, Further evidence is that treatment of cells with inhibitors of histone deacetylase was sufficient to induce transcription of integrated BCE-I in the absence of ECM. Together, these results suggest that the ECM induces a complex interaction between the enhancer-bound transcription factors, the basal transcriptional machinery, and a chromosomally integrated template responsive to the acetylation state of the histones. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. NCI, Lab Receptor Biol & Gene Express, NIH, Bethesda, MD 20892 USA. Monsanto Co, Searle Res Div, Chesterfield, MO 63017 USA. Univ Zurich Irchel, Inst Veterinarian Biochem, CH-8057 Zurich, Switzerland. RP Bissell, MJ (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, 1 Cyclotron Rd,Bldg 83-101, Berkeley, CA 94720 USA. EM mjbissell@lbl.gov RI Roskelley, Calvin /F-4630-2011 NR 66 TC 84 Z9 86 U1 0 U2 1 PU AMER SOC MICROBIOLOGY PI WASHINGTON PA 1325 MASSACHUSETTS AVENUE, NW, WASHINGTON, DC 20005-4171 USA SN 0270-7306 J9 MOL CELL BIOL JI Mol. Cell. Biol. PD APR PY 1998 VL 18 IS 4 BP 2184 EP 2195 PG 12 WC Biochemistry & Molecular Biology; Cell Biology SC Biochemistry & Molecular Biology; Cell Biology GA ZC751 UT WOS:000072613700043 PM 9528790 ER PT J AU McWhan, DB AF McWhan, DB TI Neutron and synchrotron user facilities for materials research balance need, availability, and cost SO MRS BULLETIN LA English DT Article C1 Brookhaven Natl Lab, Basic Energy Sci Program, Upton, NY 11973 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP McWhan, DB (reprint author), Brookhaven Natl Lab, Basic Energy Sci Program, Upton, NY 11973 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MATERIALS RESEARCH SOCIETY PI WARRENDALE PA 506 KEYSTONE DR, WARRENDALE, PA 15086 USA SN 0883-7694 J9 MRS BULL JI MRS Bull. PD APR PY 1998 VL 23 IS 4 BP 10 EP 10 PG 1 WC Materials Science, Multidisciplinary; Physics, Applied SC Materials Science; Physics GA ZJ047 UT WOS:000073174200012 ER PT J AU Loscher, W Liburdy, RP AF Loscher, W Liburdy, RP TI Animal and cellular studies on carcinogenic effects of low frequency (50/60-Hz) magnetic fields SO MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH LA English DT Review ID RADICAL PAIR MECHANISM; INTRACELLULAR CALCIUM OSCILLATIONS; ORNITHINE DECARBOXYLASE ACTIVITY; ELF ELECTROMAGNETIC-FIELDS; BREAST-CANCER MODEL; MOUSE-SKIN MODEL; RAT-LIVER FOCI; SIGNAL-TRANSDUCTION; BIOLOGICAL INTERACTIONS; RODENT CARCINOGENS C1 Sch Vet Med, Dept Pharmacol Toxicol & Pharm, D-30559 Hannover, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP Loscher, W (reprint author), Sch Vet Med, Dept Pharmacol Toxicol & Pharm, Bunteweg 17, D-30559 Hannover, Germany. NR 200 TC 49 Z9 53 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 1383-5742 J9 MUTAT RES-REV MUTAT JI Mutat. Res.-Rev. Mutat. Res. PD APR PY 1998 VL 410 IS 2 BP 185 EP 220 DI 10.1016/S1383-5742(97)00039-2 PG 36 WC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology SC Biotechnology & Applied Microbiology; Genetics & Heredity; Toxicology GA ZQ679 UT WOS:000073892200005 PM 9637236 ER PT J AU Heneine, W Switzer, WM Sandstrom, P Brown, J Vedapuri, S Schable, CA Khan, AS Lerche, NW Schweizer, M Neumann-Haefelin, D Chapman, LE Folks, TM AF Heneine, W Switzer, WM Sandstrom, P Brown, J Vedapuri, S Schable, CA Khan, AS Lerche, NW Schweizer, M Neumann-Haefelin, D Chapman, LE Folks, TM TI Identification of a human population infected with simian foamy viruses SO NATURE MEDICINE LA English DT Article ID T-LYMPHOTROPIC VIRUS; IMMUNODEFICIENCY-VIRUS; REVERSE-TRANSCRIPTASE; PREVALENCE; RETROVIRUS; ANTIBODY; MONKEYS; COLONY AB Studying the transmission of simian retroviruses to humans can help define the importance of these infections to public health. We identified a substantial prevalence (4/231, 1.8%) of infection with simian foamy viruses (SFV) among humans occupationally exposed to nonhuman primates. Evidence of SFV infection included seropositivity, proviral DNA detection and isolation of foamy virus. The infecting SFV originated from an African green monkey (one person) and baboons (three people), These infections have not as yet resulted in either disease or sexual transmission, and may represent benign endpoint infections. C1 Ctr Dis Control & Prevent, HIV & Retrovirol Branch, Atlanta, GA 30333 USA. Ctr Dis Control & Prevent, Immunol & Diagnost Branch, Natl Ctr Infect Dis, Atlanta, GA 30333 USA. US FDA, Ctr Biol Evaluat & Res, Lab Retrovirus Res, Bethesda, MD 20892 USA. Univ Calif Lawrence Livermore Natl Lab, Calif Reg Primate Res Ctr, Simian Retrovirus Lab, Livermore, CA 95616 USA. Univ Freiburg, Dept Virol, D-79104 Freiburg, Germany. RP Heneine, W (reprint author), Ctr Dis Control & Prevent, HIV & Retrovirol Branch, Atlanta, GA 30333 USA. NR 32 TC 161 Z9 163 U1 0 U2 6 PU NATURE AMERICA INC PI NEW YORK PA 345 PARK AVE SOUTH, NEW YORK, NY 10010-1707 USA SN 1078-8956 J9 NAT MED JI Nat. Med. PD APR PY 1998 VL 4 IS 4 BP 403 EP 407 DI 10.1038/nm0498-403 PG 5 WC Biochemistry & Molecular Biology; Cell Biology; Medicine, Research & Experimental SC Biochemistry & Molecular Biology; Cell Biology; Research & Experimental Medicine GA ZF531 UT WOS:000072906800033 PM 9546784 ER PT J AU Jordan, S Bankiewicz, KS Eberling, JL Vanbrocklin, HF O'Neil, JP Jagust, WJ AF Jordan, S Bankiewicz, KS Eberling, JL Vanbrocklin, HF O'Neil, JP Jagust, WJ TI An in vivo microdialysis study of striatal 6-[F-18]fluoro-L-m-tyrosine metabolism SO NEUROCHEMICAL RESEARCH LA English DT Article DE amphetamine; 6-[F-18]fluoro-L-m-tyrosine; metabolism; microdialysis; PET; striatum ID DOPAMINE; AMPHETAMINE; RELEASE; BIOCHEMISTRY; NEURONS; BRAIN AB In vivo brain microdialysis was used to monitor 6-[F-18]fluoro-L-m-tyrosine (FMT) uptake and metabolism in the striatum of conscious freely moving rats for 3 hours after FMT injection (25 mg/kg, iv). Microdialysate collected 20 to 120 min post-dose, contained FMT at a concentration (0.2 to 0.3 nM) approximately ten-fold below that of its metabolite [F-18]fluoro-3-hydroxyphenylacetic acid (FPAC; 3.2 to 3.3 nM). D-amphetamine (2.5 mg/kg, i.p.) injected 120 min after significantly increased microdialysate FPAC (3.27 +/- 0.31 nM to 4.51 +/- 0.45 nM) in control but not reserpinized rats. Taken together these data demonstrate FMT is heavily metabolized following its entry into the striatum yielding FPAC which appears to be stored, at least in part, in reserpine sensitive cytoplasmic vesicles. Presynaptic retention of FPAC may contribute to the preferential accumulation of FMT positron emission tomography (PET) signaling in dopaminergic brain areas. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Somatix Therapy Corp, Alameda, CA 94501 USA. Univ Calif Davis, Dept Neurol, Davis, CA 95616 USA. RP Jordan, S (reprint author), Warner Lambert Co, Parke Davis Pharmaceut Res Div, Dept Pharmacokinet & Drug Metab, 2800 Plymouth Rd, Ann Arbor, MI 48105 USA. NR 21 TC 11 Z9 11 U1 0 U2 0 PU PLENUM PUBL CORP PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 0364-3190 J9 NEUROCHEM RES JI Neurochem. Res. PD APR PY 1998 VL 23 IS 4 BP 513 EP 517 DI 10.1023/A:1022478417383 PG 5 WC Biochemistry & Molecular Biology; Neurosciences SC Biochemistry & Molecular Biology; Neurosciences & Neurology GA ZG668 UT WOS:000073027200008 PM 9566585 ER PT J AU Tabak, M Callahan-Miller, D Ho, DDM Zimmerman, GB AF Tabak, M Callahan-Miller, D Ho, DDM Zimmerman, GB TI Design of a distributed radiator target for inertial fusion driven from two sides with heavy ion beams SO NUCLEAR FUSION LA English DT Article ID IGNITION; PHYSICS; GAIN AB A distributed-radiator heavy ion target design is described. In two dimensional LASNEX (G.B. Zimmerman, W.B. Kruer, Comments Plasma Phys. Control. Fusion 2 (1975) 83) calculations that integrate the physics of ion beam deposition and hohlraum dynamics, including radiation and material flow, with the implosion and thermonuclear burn of an inertial confinement fusion (ICF) capsule, the capsule ignited and produced 430 MJ of yield when driven with 6.5 MJ of 3 to 4 GeV lead ions. The target has cylindrical symmetry with disc endplates of 5 mm radius. The ions uniformly illuminate these endplates from two sides. The considerations that led to this design, together with some previously unused design features, are discussed: low density hohlraum walls in approximate pressure balance with internal low-Z fill materials, radiation symmetry determined by the position of the radiator materials and particle ranges, and early time pressure symmetry, possibly influenced by radiation shims. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Tabak, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 20 TC 34 Z9 34 U1 1 U2 2 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD APR PY 1998 VL 38 IS 4 BP 509 EP 513 DI 10.1088/0029-5515/38/4/303 PG 5 WC Physics, Fluids & Plasmas SC Physics GA ZN514 UT WOS:000073653500003 ER PT J AU Barnes, CW Bosch, HS Hendel, HW Huibers, AGA Jassby, DL Motley, RW Nieschmidt, EB Saito, T Strachan, JD Bitter, M Budny, RV Hill, KW Mansfield, DK McCune, DC Nazikian, R Park, HK Ramsey, AT Scott, SD Taylor, G Zarnstorff, MC AF Barnes, CW Bosch, HS Hendel, HW Huibers, AGA Jassby, DL Motley, RW Nieschmidt, EB Saito, T Strachan, JD Bitter, M Budny, RV Hill, KW Mansfield, DK McCune, DC Nazikian, R Park, HK Ramsey, AT Scott, SD Taylor, G Zarnstorff, MC TI Triton burnup measurements and calculations on TFTR SO NUCLEAR FUSION LA English DT Article ID FUSION TEST REACTOR; ELECTRON-CYCLOTRON EMISSION; NEUTRON-ACTIVATION SYSTEM; RAY CRYSTAL SPECTROMETER; ABEL-INVERSION METHOD; MICHELSON INTERFEROMETER; RESOLVED MEASUREMENTS; RADIAL DIFFUSION; ION TEMPERATURE; PLASMA ROTATION AB Measurements of the burnup of fusion product tritons in TFTR are presented. Interpretation of triton burnup experiments requires three accurate components: the measurement of the 2.5 MeV neutron emission, the measurement of the 14 MeV neutron emission and a calculation of the expected burnup ratio from the measured plasma parameters. The absolute calibration for the 14 MeV neutron measurements is provided by an NE213 proton recoil spectrometer. Time dependent burnup measurements for three plasma conditions selected for optimum detector operation are shown. Measurements of the time integrated triton burnup from copper activation foils (cross-calibrated to the NE213 measurements) are presented. Descriptions are provided of the neutron detectors and the plasma diagnostics whose data are used as input to the calculation of the expected burnup. All these measurements find that the triton burnup on TFTR is 1/2 +/- 1/4 the classical expectations for a wide variety of discharges. The burnup decreases for relatively longer triton slowing down times, implying possible fast ion diffusion coefficients of similar to 0.1 m(2)/s. Alternatively, burnup appears to decrease with increasing major radius of the triton source and edge safety factor q(cyl), implying that ripple losses may be playing a role. Triton burnup is a very sensitive measure of anomalous fast ion transport; similar levels of diffusive transport in an ignited reactor would have minimal impact on the alpha particles. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Barnes, CW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. EM cbarnes@lanl.gov RI Bosch, Hans-Stephan/F-9527-2015 NR 76 TC 6 Z9 6 U1 1 U2 5 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD APR PY 1998 VL 38 IS 4 BP 597 EP 618 DI 10.1088/0029-5515/38/4/310 PG 22 WC Physics, Fluids & Plasmas SC Physics GA ZN514 UT WOS:000073653500010 ER PT J AU Fournier, KB Pacella, D May, MJ Finkenthal, M Goldstein, WH AF Fournier, KB Pacella, D May, MJ Finkenthal, M Goldstein, WH TI Calculation of the radiative cooling coefficient for molybdenum in a low density plasma (vol 37, pg 825, 1997) SO NUCLEAR FUSION LA English DT Correction C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EURATOM Assoc, Ctr Ric Frascati, ENEA Fus, Frascati, Italy. Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RP Fournier, KB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 1 TC 7 Z9 7 U1 1 U2 4 PU INT ATOMIC ENERGY AGENCY PI VIENNA PA WAGRAMERSTRASSE 5, PO BOX 100, A-1400 VIENNA, AUSTRIA SN 0029-5515 J9 NUCL FUSION JI Nucl. Fusion PD APR PY 1998 VL 38 IS 4 BP 639 EP 640 DI 10.1088/0029-5515/38/4/513 PG 2 WC Physics, Fluids & Plasmas SC Physics GA ZN514 UT WOS:000073653500013 ER PT J AU Beuville, E Cederstrom, B Danielsson, M Luo, L Nygren, D Oltman, E Vestlund, J AF Beuville, E Cederstrom, B Danielsson, M Luo, L Nygren, D Oltman, E Vestlund, J TI An application specific integrated circuit and data acquisition system for digital X-ray imaging SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB We have developed an Application Specific Integrated Circuit (ASIC) and data acquisition system for digital X-ray imaging. The chip consists of 16 parallel channels, each containing preamplifier, shaper, comparator and a 16 bit counter. We have demonstrated noiseless single-photon counting over a threshold of 7.2 keV using Silicon detectors and are presently capable of maximum counting rates of 2 MHz per channel. The ASIC is controlled by a personal computer through a commercial PCI card, which is also used for data acquisition. The content of the 16 bit counters are loaded into a shift register and transferred to the PC at any time at a rate of 20 MHz. The system is non-complicated, low cost and high performance and is optimised for digital X-ray imaging applications. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Lawrence Berkeley Lab, Berkeley, CA 94707 USA. RP Danielsson, M (reprint author), Lawrence Berkeley Lab, 1 Cyclotron Rd,MS 50-208, Berkeley, CA 94707 USA. NR 10 TC 31 Z9 31 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD APR 1 PY 1998 VL 406 IS 2 BP 337 EP 342 DI 10.1016/S0168-9002(97)01216-3 PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZH813 UT WOS:000073150200014 ER PT J AU Charlton, WS Perry, RT Wilson, WB AF Charlton, WS Perry, RT Wilson, WB TI Benchmarking of the Los Alamos neutron production rate code SOURCES-3A SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article DE alpha reactions; spontaneous fission; delayed neutrons; actinide isotopes; neutron production ID LIGHT-ELEMENTS; YIELDS AB The neutron production rate code SOURCES-3A was benchmarked using various experimental measurements from the literature. These experiments included thick-target yield measurements from Li, Be, B, C, O, F, Mg, Al, Si, UO2, and UC. Several integrated experiments (PuBe13 and UO2F2 homogeneous problems, Po-B4C and Po-Be interface problems, and Al2O3 and SiO2 beam problems) were also modeled, testing all the geometry characteristics of the SOURCES-3A code. The SOURCES-3A calculations were compared with the experimental results and good agreement was found in all cases. These benchmarks have shown that SOURCES-3A spectra and magnitude calculations are accurate to within +/-18% for even the most complex problems. (C) 1998 Elsevier Science B.V. C1 Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Charlton, WS (reprint author), Texas A&M Univ, Dept Nucl Engn, College Stn, TX 77843 USA. NR 17 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD APR PY 1998 VL 140 IS 1-2 BP 1 EP 8 DI 10.1016/S0168-583X(98)00012-3 PG 8 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZT169 UT WOS:000074056100001 ER PT J AU Sckerl, MW Lam, NQ Sigmund, P AF Sckerl, MW Lam, NQ Sigmund, P TI Compositional changes in alloys during ion bombardment at elevated temperatures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article ID SURFACE SEGREGATION; ENHANCED DIFFUSION; IRRADIATION; METALS AB Near-surface compositional changes in alloys during ion bombardment have been studied theoretically. The employed scheme operates with a stable target, and the effects of preferential sputtering, collisional mixing, radiation-enhanced diffusion, and Gibbsian and radiation-induced segregation are allowed for. High-fluence composition profiles were determined directly from a nonlinear integro-differential equation, after insertion of feasible input, by means of an efficient iteration procedure developed recently. The dependence of the composition profile on input parameters such as target temperature and defect mobility has been examined for Ni-Cu, Ni-Ge and Ni-Pd alloys and compared to experimental results. (C) 1998 Elsevier Science B.V. C1 Odense Univ, Dept Phys, DK-5230 Odense M, Denmark. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Sckerl, MW (reprint author), Tech Univ Denmark, Mikroelekt Ctr, DK-2800 Lyngby, Denmark. RI Sigmund, Peter/B-1115-2012 OI Sigmund, Peter/0000-0002-2959-1305 NR 42 TC 11 Z9 13 U1 2 U2 6 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD APR PY 1998 VL 140 IS 1-2 BP 75 EP 90 DI 10.1016/S0168-583X(97)00927-0 PG 16 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZT169 UT WOS:000074056100010 ER PT J AU Chan, KCD Lawrence, GP Schneider, JD AF Chan, KCD Lawrence, GP Schneider, JD TI Development of RF linac for high-current applications SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 5th European Conference on Accelerators in Applied Research and Technology (ECAART5) CY AUG 26-30, 1997 CL EINDHOVEN UNIV, EINDHOVEN, NETHERLANDS HO EINDHOVEN UNIV DE accelerator; tritium; superconducting; application AB High-current proton linacs are promising sources of neutrons for material processing and research applications. Recently. a linac design that makes use of a combination of normal-conducting (NC) and superconducting (SC) linac technologies has been proposed for the US Accelerator Production of Tritium (APT) Project. As a result, a multi-year engineering development and demonstration (ED&D) program is underway. In this paper, we will describe the design and merits of the NC/SC hybrid approach. The scope, technology issues, and present status of the ED&D Program, and the participation of industry will also be described. (C) 1998 Elsevier Science B.V. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Chan, KCD (reprint author), Los Alamos Natl Lab, MS H816, Los Alamos, NM 87544 USA. EM kcchan@lanl.gov NR 9 TC 1 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD APR PY 1998 VL 139 IS 1-4 BP 394 EP 400 DI 10.1016/S0168-583X(97)00939-7 PG 7 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZY096 UT WOS:000074586200065 ER PT J AU Cline, DB Garren, A Green, M Kolonko, J Lee, K AF Cline, DB Garren, A Green, M Kolonko, J Lee, K TI An ultra-compact hard X-ray superconducting light source for biotechnology and industrial use SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS LA English DT Article; Proceedings Paper CT 5th European Conference on Accelerators in Applied Research and Technology (ECAART5) CY AUG 26-30, 1997 CL EINDHOVEN UNIV, EINDHOVEN, NETHERLANDS HO EINDHOVEN UNIV AB We describe the design of a 1.5-GeV ultra-compact storage ring that uses 7-T superconducting magnets. The aim of this source is to provide intense 10-30 keV X-rays of moderate brilliance for commercial application. The first prototype is being designed for the UCLA Science and Technology Research Building (STRB) in Weslwood, California. (C) 1998 Elsevier Science B.V. C1 Univ Calif Los Angeles, Ctr Adv Accelerators, Los Angeles, CA 90095 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Engn, Berkeley, CA 94720 USA. RP Cline, DB (reprint author), Univ Calif Los Angeles, Ctr Adv Accelerators, Knudsen Hall,Box 951547, Los Angeles, CA 90095 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-583X J9 NUCL INSTRUM METH B JI Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms PD APR PY 1998 VL 139 IS 1-4 BP 531 EP 536 DI 10.1016/S0168-583X(98)00024-X PG 6 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical; Physics, Nuclear SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZY096 UT WOS:000074586200092 ER PT J AU Bergstrom, KA Halldin, C Hiltunen, J Swahn, CG Ito, H Ginovart, N Hall, H McPherson, DW Knapp, FFR Larsson, S Schnell, PO Farde, L AF Bergstrom, KA Halldin, C Hiltunen, J Swahn, CG Ito, H Ginovart, N Hall, H McPherson, DW Knapp, FFR Larsson, S Schnell, PO Farde, L TI Evaluation and metabolite studies of I-125- and I-123-labelled E-(R,R)-IQNP: Potential radioligands for visualization of M-1 muscarinic acetylcholine receptors in brain SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE E-(R,R)-IQNP; muscarinic acetylcholine receptors; brain; SPET; autoradiography ID IODINE-125-LABELED 1-AZABICYCLO<2.2.2>OCT-3-YL ALPHA-HYDROXY-ALPHA-(1-IODO-1-PRO; EMISSION COMPUTED-TOMOGRAPHY; HIGH-AFFINITY; D-2-DOPAMINE RECEPTORS; BINDING; LIGAND; D-1-DOPAMINE; ALZHEIMERS; BIPERIDEN; INVIVO AB A new ligand for the M-1 muscarinic receptor subtype, E-(R,R)-1-azabicyclo[2.2.2]oct-3-yl alpha-hydroxy-alpha-(1-iodo-1-propen-3-yl)-alpha-phenylacetate (E-IQNP), was labelled with I-125 and I-123 for autoradiographic studies on human whole-brain cryosections and SPET studies, respectively, in Cynomolgus monkey. Autoradiography demonstrated E-[I-125]IQNP binding in M-1 receptor-rich regions such as the neocortex and the striatum. The binding was displaceable by the selective M-1 antagonist biperiden. In vivo single photon emission tomography (SPET) studies with E-[I-123]IQNP demonstrated a high accumulation of radioactivity in the monkey neocortex, Rapid hydrolysis of the quinuclidinyl ester to the free acid was found to be a major biotransformation route for E-[I-123]IQNP. The free acid of E-[I-123]IQNP does not pass the blood-brain barrier, but the plasma concentration was high as compared to the total radioactivity in brain. It is thus necessary to correct for the high concentration of radioactive metabolites in parenchymal blood (CBV) to obtain accurate values for E-[I-123]IQNP binding in brain. (C) 1998 Elsevier Science Inc. C1 Kuopio Univ Hosp, Dept Clin Physiol, FIN-70210 Kuopio, Finland. Karolinska Hosp & Inst, Dept Clin Neurosci, Psychiat Sect, S-17176 Stockholm, Sweden. Karolinska Hosp & Inst, Dept Clin Neurosci, Nucl Med Sect, S-17176 Stockholm, Sweden. Map Med Technol, FIN-41160 Tikkakoski, Finland. Oak Ridge Natl Lab, Nucl Med Grp, Oak Ridge, TN 37831 USA. RP Bergstrom, KA (reprint author), Kuopio Univ Hosp, Dept Clin Physiol, FIN-70210 Kuopio, Finland. FU NIMH NIH HHS [NIMH 41205] NR 22 TC 6 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD APR PY 1998 VL 25 IS 3 BP 209 EP 214 DI 10.1016/S0969-8051(97)00198-4 PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZE898 UT WOS:000072842700007 PM 9620625 ER PT J AU Kennel, SJ Mirzadeh, S AF Kennel, SJ Mirzadeh, S TI Vascular targeted radioimmunotherapy with Bi-213 - An alpha-particle emitter SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE Bi-213; lung; vasculature; carcinoma; alpha particles; solid tumor; targeted ID MONOCLONAL-ANTIBODIES; TUMOR-GROWTH; ENDOTHELIAL-CELLS; EPITHELIAL-CELLS; SOLID TUMORS; INHIBITION; ANGIOGENESIS; THERAPY; METASTASIS; INVIVO AB To destroy both tumor blood vessels and adjacent tumor cells, an cu particle emitter, Bi-213, has been targeted with a monoclonal antibody (MAb) to vessels that feed lung tumors in mice. Animals, bearing approximately 100 EMT-6 carcinomas each of 50-400 cells in size in the lung, that were treated with 120 mu Ci of Bi-213-MAb 201B were all cured of their disease, Animals treated when tumors were larger (10(3)-10(4) cells) had extended life spans, but a small number of residual tumors eventually killed the animals. Significant extension of life span was also induced with another tumor model - rat tracheal carcinoma growing in the lungs of SCID mice that were then treated with 136 mu Ci Bi-213-MAb B-201. These studies indicate that attack of both blood vessels and tumor cells simultaneously is an effective mode of cancer treatment. (C) 1998 Elsevier Science Inc. C1 Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Kennel, SJ (reprint author), Oak Ridge Natl Lab, Div Life Sci, POB 2009, Oak Ridge, TN 37831 USA. NR 29 TC 57 Z9 59 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD APR PY 1998 VL 25 IS 3 BP 241 EP 246 DI 10.1016/S0969-8051(97)00200-X PG 6 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZE898 UT WOS:000072842700011 PM 9620629 ER PT J AU Swailem, FM Krishnamurthy, GT Srivastava, SC Aguirre, ML Ellerson, DL Walsh, TK Simpson, L AF Swailem, FM Krishnamurthy, GT Srivastava, SC Aguirre, ML Ellerson, DL Walsh, TK Simpson, L TI In-vivo tissue uptake and retention of Sn-117m(4+)DTPA in a human subject with metastatic bone pain and in normal mice SO NUCLEAR MEDICINE AND BIOLOGY LA English DT Article DE bone pain palliation; Sn-117m(4+)DTPA; retention; clearance; soft tissue ID INVIVO BEHAVIOR; BIODISTRIBUTION; CANCER; RADIOPHARMACEUTICALS; SAMARIUM-153-EDTMP; PHARMACOKINETICS; ANIMALS; TIN AB Organ and tissue uptake and retention of Sn-117m(4+)DTPA were studied in a human subject treated for metastatic bone pain, and the results were compared with the biodistribution studies in five normal mice. The explanted organs from a patient who received a therapy dose of 18.6 mCi (688.2 MBq) Sn-117m(4+)DTPA and who died 47 days later were imaged with a gamma-camera, and tissue samples were counted and also autoradiographed. Bone, muscle, liver, fat, lungs, kidneys, spleen, heart and pancreas tissue samples were assayed in a well counter for radioactivity. Regions of interest were drawn over bone and major organs to calculate and quantify clearance times using three in vivo Sn-117m(4+)DTPA whole-body scintigrams acquired at 1, 24 and 168 h after injection. Five normal mice injected with the same batch of Sn-117m(4+)DTPA as used for the human subject were sacrificed at 24 h, and tissue samples were collected and assayed for radioactivity for comparison with the human data. For the human subject, whole body retention at 47 days postinjection was 81% of the injected dose, and the rest (19%) was excreted in urine. Of the whole body retained activity at 47 days, 82.4% was in bone, 7.8% in the muscle and 1.5% in the liver, and the rest was distributed among other tissues. gamma-Ray scintigrams and electron autoradiographs of coronal slices of the thoracolumbar vertebral body showed heterogenous metastatic involvement with normal bone between metastatic lesions. There was nonuniform distribution of radioactivity even within a single vertebral body, indicating normal bone between metastatic lesions. Lesion to nonlesion ratios ranged from 3 to 5. However, the osteoid-to-marrow cavity deposition ratio, from the microautoradiographs, was 11:1. The peak uptake in the human bone was seen at 137 h with no biological clearance. Soft tissues showed peak uptake at 1 h and exhibited three compartmental clearance components. Whole body retention in normal mice was 38.7% of the injected dose at 24 h and the rest was excreted. At 24 h postinjection, bone in mice showed 84.2% of the whole-body retention, muscle 1.7% and liver 1.4%, and the rest was distributed in other soft tissues. Percent distribution of the retained dose among bone, muscle, liver and other soft tissues is very similar between mice and a human subject. To calculate precise radiation absorbed doses from bone pain palliation radionuclides, it is necessary to take into account soft tissue uptake and retention that may not be readily evident from routine external gamma-scintigraphy. Published by Elsevier Science Inc. C1 Vet Adm Med Ctr, Imaging Serv, Tucson, AZ 85723 USA. Univ Arizona, Sch Med, Dept Radiol, Tucson, AZ USA. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Swailem, FM (reprint author), Vet Adm Med Ctr, Nucl Med Serv 115, Tucson, AZ 85723 USA. NR 15 TC 19 Z9 22 U1 0 U2 0 PU ELSEVIER SCIENCE INC PI NEW YORK PA 655 AVENUE OF THE AMERICAS, NEW YORK, NY 10010 USA SN 0969-8051 J9 NUCL MED BIOL JI Nucl. Med. Biol. PD APR PY 1998 VL 25 IS 3 BP 279 EP 287 DI 10.1016/S0969-8051(97)00180-7 PG 9 WC Radiology, Nuclear Medicine & Medical Imaging SC Radiology, Nuclear Medicine & Medical Imaging GA ZE898 UT WOS:000072842700016 PM 9620634 ER PT J AU Bhattacharya, T Gupta, R AF Bhattacharya, T Gupta, R TI Advances in the determination of quark masses SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID LATTICE QCD; WILSON FERMIONS; CHIRAL-SYMMETRY AB Significant progress has been made in the determination of the light quark masses, using both lattice QCD and sum rule methods, in the last year. We discuss the different methods and review the status of current results. Finally, we review the calculation of bottom and charm masses. C1 Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, MS B285,T-8, Los Alamos, NM 87545 USA. EM rajan@qcd.lanl.gov RI Bhattacharya, Tanmoy/J-8956-2013 OI Bhattacharya, Tanmoy/0000-0002-1060-652X NR 48 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 95 EP 107 DI 10.1016/S0920-5632(97)00701-9 PG 13 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200013 ER PT J AU Bardeen, W Duncan, A Eichten, E Hockney, G Thacker, H AF Bardeen, W Duncan, A Eichten, E Hockney, G Thacker, H TI Resolving exceptional configurations SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID WILSON FERMIONS; LATTICE QCD; U(1) PROBLEM; LIMIT AB In lattice QCD with Wilson fermions, exceptional configurations arise in the quenched approximation at small quark mass. The origin of these large previously uncontrolled lattice artifacts is identified. A simple well-defined procedure (MQA) is presented which removes the artifacts while preserving the correct continuum limit. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. CALTECH, Jet Prop Lab, Pasadena, CA 91109 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM tony@dectony.phyast.pitt.edu; eichten@fnal.gov; thacker@virginia.edu NR 17 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 141 EP 146 DI 10.1016/S0920-5632(97)00705-6 PG 6 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200017 ER PT J AU Bardeen, W Duncan, A Eichten, E Perrucci, S Thacker, H AF Bardeen, W Duncan, A Eichten, E Perrucci, S Thacker, H TI The eta ' propagator in quenched QCD SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID LATTICE; U(1) AB The calculation of the eta' hairpin diagram is carried out in the modified quenched approximation (MQA) in which the lattice artifact which causes exceptional configurations is removed by shifting observed poles at kappa < kappa(c) in the quark propagators to the critical value of hopping parameter. By this method, the eta' propagator can be accurately calculated even for very light quark mass. A determination of the topological susceptibility for quenched QCD is also obtained, using the fermionic method of Smit and Vink to calculate winding numbers. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. EM tony@dectony.phyast.pitt.edu; eichten@fnal.gov; thacker@virginia.edu NR 7 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 191 EP 193 DI 10.1016/S0920-5632(97)00718-4 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200030 ER PT J AU Lee, W Weingarten, D AF Lee, W Weingarten, D TI The scalar quarkonium spectrum and quarkonium-glueball mixing SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID LATTICE AB We evaluate the valence approximation to the mass of scalar quarkonium and to the mixing energy between scalar quarkonium and the lightest scalar glueball for a range of different lattice sizes and quark masses. Our results support the identification of f(0)(1710) as the lightest scalar glueball. C1 IBM Corp, Thomas J Watson Res Ctr, Res, Yorktown Hts, NY 10598 USA. RP Los Alamos Natl Lab, T-8, Los Alamos, NM 87545 USA. EM wlee@watson.ibm.com; weingar@watson.ibm.com NR 12 TC 33 Z9 33 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 194 EP 196 DI 10.1016/S0920-5632(97)00719-6 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200031 ER PT J AU Bernard, C Blum, T DeGrand, TA DeTar, C Gottlieb, S Heller, UM Hetrick, J McNeile, C Rummukainen, K Sugar, R Toussaint, D AF Bernard, C Blum, T DeGrand, TA DeTar, C Gottlieb, S Heller, UM Hetrick, J McNeile, C Rummukainen, K Sugar, R Toussaint, D TI Update on the hadron spectrum with two flavors of staggered quarks SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB We present an update on the MILC Collaboration's light hadron spectrum calculation with two flavors of dynamical, staggered quarks. Results are presented for gauge couplings 5.30, 5.415, 5.50 and 5.60, with a range of quark masses for each value of the coupling. We present extrapolations of m(N)/m(rho) to the continuum limit for fixed values of m(pi)/m(rho) including the physical one. C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Univ Bielefeld, Fak Phys, D-33501 Bielefeld, Germany. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. RP Washington Univ, Dept Phys, St Louis, MO 63130 USA. EM cb@lump.wustl.edu; tblum@wind.phy.bnl.gov; degrand@aurinko.colorado.edu; detar@physics.utah.edu; sg@fuji.physics.indiana.edu; heller@scri.fsu.edu; hetrick@jdub.wustl.edu; mcneile@mail.physics.utah.edu; kari@physik.uni-bielefeld.de; sugar@sakar.physics.ucsb.edu; doug@physics.arizona.edu OI Hetrick, James/0000-0002-0740-2251; Heller, Urs M./0000-0002-2780-5584; DeTar, Carleton/0000-0002-0216-6771; Rummukainen, Kari/0000-0003-2266-4716 NR 3 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 215 EP 217 DI 10.1016/S0920-5632(97)00726-3 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200038 ER PT J AU Gupta, R AF Gupta, R TI B-parameters of 4-fermion operators from lattice QCD SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB This talk summarizes the status of the calculations of B-K, B-7, B-8, and B-s, done in collaboration with T. Bhattacharya, G. Kilcup, and S. Sharpe. Results for staggered, Wilson, and Clover fermions are presented. C1 Los Alamos Natl Lab, Grp T8, Los Alamos, NM 87545 USA. RP Los Alamos Natl Lab, Grp T8, MS B-285, Los Alamos, NM 87545 USA. EM rajan@qcd.lanl.gov NR 7 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 278 EP 280 DI 10.1016/S0920-5632(97)00745-7 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200056 ER PT J AU Blum, T Soni, A AF Blum, T Soni, A TI Lattice QCD with domain wall quarks and applications to weak matrix elements SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID CHIRAL FERMIONS AB Using domain wall fermions, we estimate B-K(mu approximate to 2 GeV) = 0.628(47) in quenched QCD which is consistent with previous calculations. At 6/g(2) = 6.0 and 5.85 we find the ratio f(K)/m(rho) in agreement with the experimental value, within errors. These results support expectations that O(a) errors are exponentially suppressed in low energy (E much less than a(-1)) observables, and indicate that domain wall fermions have good scaling behavior at relatively strong couplings. We also demonstrate that the axial current numerically satisfies the lattice analog of the usual continuum axial Ward identity. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. EM tblum@penguin.phy.bnl.gov; soni@penguin.phy.bnl.gov NR 13 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 287 EP 289 DI 10.1016/S0920-5632(97)00748-2 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200059 ER PT J AU Mackenzie, PB Ryan, SM Simone, JN AF Mackenzie, PB Ryan, SM Simone, JN TI Spectroscopy of B-s and D-s mesons SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID QCD AB We study B-s and D-s spectroscopy in quenched lattice QCD using the Fermilab approach to heavy quarks. We obtain results at four lattice spacings, a, using O(a)-improved Wilson quarks. We compare and contrast the various methods for heavy quarks on the lattice, discussing discussing which methods work best for different physical systems and the ease with which calculations may be performed. C1 Fermilab Natl Accelerator Lab, Theoret Phys Grp, Batavia, IL 60510 USA. Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA. RP Fermilab Natl Accelerator Lab, Theoret Phys Grp, POB 500, Batavia, IL 60510 USA. EM mackenzie@fnal.gov; sinead@fnal.gov; simone@PObox.hep.uiuc.edu NR 15 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 305 EP 310 DI 10.1016/S0920-5632(97)00753-6 PG 6 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200064 ER PT J AU Kronfeld, AS AF Kronfeld, AS TI The charm quark's mass SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB The charm quark's mass is determined from Monte Carlo calculations of the Ec spectrum. The main sources of uncertainty are perturbation theory (for conversion to <(MS)over bar>), the continuum-limit extrapolation, Monte Carlo statistics, and the effects of quenching. The (preliminary) result for the <(MS)over bar> mass is <(m)over bar (ch)>(m(ch)) = 1.33 +/- 0.08 GeV. C1 Fermilab Natl Accelerator Lab, Theoret Phys Grp, Univ Res Assoc Inc, Batavia, IL 60510 USA. RP Fermilab Natl Accelerator Lab, Theoret Phys Grp, Univ Res Assoc Inc, POB 500, Batavia, IL 60510 USA. EM ask@fnal.gov OI Kronfeld, Andreas/0000-0003-2716-1149 NR 12 TC 19 Z9 19 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 311 EP 313 DI 10.1016/S0920-5632(97)00754-8 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200065 ER PT J AU Ryan, SM Simone, JN AF Ryan, SM Simone, JN TI Decay constants of heavy-light pseudoscalar mesons in the Fermilab formalism SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB We present new results from the Fermilab weak matrix-element project. The decay constants of heavy-light pseudoscalar mesons are calculated using the Fermilab formalism for heavy quarks and a tadpole-improved SW action for light quarks. Improvement allows the bottom quark to be simulated directly on the lattice removing the need for large extrapolations. The dependence on the lattice spacing is discussed for 5.7 less than or equal to beta less than or equal to 6.1. C1 Fermi Natl Accelerator Lab, Theoret Phys Grp, Batavia, IL 60510 USA. Univ Illinois, Loomis Lab Phys, Urbana, IL 61801 USA. RP Ryan, SM (reprint author), Fermi Natl Accelerator Lab, Theoret Phys Grp, POB 500, Batavia, IL 60510 USA. EM sinead@fnal.gov; simone@PObox.hep.uiuc.edu NR 5 TC 2 Z9 2 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 353 EP 355 DI 10.1016/S0920-5632(97)00767-6 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200078 ER PT J AU Bernard, C Blum, T DeTar, CE Gottlieb, S Heller, UM Hetrick, JE Jegerlehner, B Rummukainen, K Sugar, RL Toussaint, D Wingate, M AF Bernard, C Blum, T DeTar, CE Gottlieb, S Heller, UM Hetrick, JE Jegerlehner, B Rummukainen, K Sugar, RL Toussaint, D Wingate, M TI Critical behavior at the chiral phase transition SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID 2-FLAVOR C1 Washington Univ, Dept Phys, St Louis, MO 63130 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Utah, Dept Phys, Salt Lake City, UT 84112 USA. Univ Bielefeld, Zentrum Interdisziplinare Forsch, D-4800 Bielefeld, Germany. Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Univ Bielefeld, Fak Phys, D-33501 Bielefeld, Germany. Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA. Univ Arizona, Dept Phys, Tucson, AZ 85721 USA. Univ Tsukuba, Ctr Computat Phys, Tsukuba, Ibaraki 305, Japan. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. RP Bernard, C (reprint author), Washington Univ, Dept Phys, St Louis, MO 63130 USA. OI Hetrick, James/0000-0002-0740-2251; Heller, Urs M./0000-0002-2780-5584; Wingate, Matthew/0000-0001-6568-988X; DeTar, Carleton/0000-0002-0216-6771; Rummukainen, Kari/0000-0003-2266-4716 NR 8 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 400 EP 402 DI 10.1016/S0920-5632(97)00782-2 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200093 ER PT J AU Kogut, JB Lagae, JF Sinclair, DK AF Kogut, JB Lagae, JF Sinclair, DK TI Topology, fermionic zero modes and flavor singlet correlators in finite temperature QCD. SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID THERMODYNAMICS AB We extend our earlier results concerning the breaking of the U-A(1) symmetry in finite temperature QCD. In particular, we use topological argments to investigate the chiral limit. C1 Univ Illinois, Dept Phys, Urbana, IL 61801 USA. Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Univ Illinois, Dept Phys, 1110 W Green St, Urbana, IL 61801 USA. EM lagae@hep.anl.gov; dks@hep.anl.gov NR 9 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 433 EP 435 DI 10.1016/S0920-5632(97)00793-7 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200104 ER PT J AU Creutz, M AF Creutz, M TI Is the doubler of the electron an antiquark? SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID CHIRAL FERMIONS; LATTICE; ANOMALIES; SYMMETRY AB Reassigning degrees of freedom in the standard model allows an interpretation where the SU(2) gauge group is vector-like and parity violation moves to the strong and electromagnetic interactions. In this picture, the electron is paired with an anti-quark. Requiring exact gauge invariance for the electromagnetic interaction clarifies the mechanism behind a recent proposal for a lattice regularization of the standard model. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Creutz, M (reprint author), Brookhaven Natl Lab, Dept Phys, POB 5000, Upton, NY 11973 USA. NR 14 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 599 EP 601 DI 10.1016/S0920-5632(97)00844-X PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200155 ER PT J AU Weinstein, M AF Weinstein, M TI Probing The CORE of the Haldane Conjecture SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID HEISENBERG AB The COntractor REnormalization group method (CORE), originally developed for application to lattice gauge theories, is very well adapted the study of spin systems and systems with fermions. As an warmup exercise for studying Hubbard models this method is applied to spin-1/2 and spin-1 anti-ferromagnets in one space dimension in order to see if it is able to explain the physics of the Haldane conjecture. The method not only provides support for Haldane's conjecture but provides insight into the physics of a more general class of spin-1 systems with Hamiltonians of the form H = Sigma(j) (s) over right arrow s(j).(s) over right arrow(j + 1) - beta((s) over right arrow(j).(s) over right arrow(j + 1))(2) about which, until now, little was known. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Weinstein, M (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 3 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 661 EP 663 DI 10.1016/S0920-5632(97)00864-5 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200175 ER PT J AU Bardeen, W Duncan, A Eichten, E Thacker, H AF Bardeen, W Duncan, A Eichten, E Thacker, H TI QED2 as a testbed for interpolations between quenched and full QCD SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB Lattice QED2 with the Wilson formulation of fermions is used as a convenient model system to study artifacts of the quenched approximation on a finite lattice. The quenched functional integral is shown to be ill-defined in this system as a consequence of the appearance of exactly real modes for physical values of the fermion mass. The location and frequency of such modes is studied as a function of lattice spacing, lattice volume, topological charge and improved action parameters. The efficacy of the recently proposed modified quenched approximation is examined, as well as a new approach to the interpolation from the quenched to full dynamical theory employing a truncated form of the fermion determinant. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Bardeen, W (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 811 EP 813 DI 10.1016/S0920-5632(97)00908-0 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200219 ER PT J AU Lagae, JF Sinclair, DK AF Lagae, JF Sinclair, DK TI Improving the staggered quark action to reduce flavour symmetry violations. SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh ID QCD AB We investigate a class of actions for lattice QCD with staggered quarks aimed at reducing the flavour symmetry violations associated with using staggered fermions. These actions replace the gauge field link fields in the quark action with covariantly smeared fields. As such they are an extension of actions considered by the MILC collaboration. We show that such actions systematically reduce flavour symmetry violations in the weak coupling Limit. Using the mass splitting between Goldstone and non-Goldstone pions as a measure of flavour symmetry violations we find that these actions have considerably less flavour symmetry violations than the standard staggered action, and represent an improvement on what can be achieved with the MILC action, on quenched configurations with beta = 5.7. C1 Argonne Natl Lab, Div High Energy Phys, Argonne, IL 60439 USA. RP Argonne Natl Lab, Div High Energy Phys, 9700 S Cass Ave, Argonne, IL 60439 USA. EM lagae@hep.anl.gov NR 9 TC 23 Z9 23 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 892 EP 894 DI 10.1016/S0920-5632(97)00932-8 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200243 ER PT J AU Chen, D Chen, P Christ, NH Edwards, RG Fleming, GR Gaza, A Hansen, S Jung, C Kaehler, AL Kennedy, AD Kilcup, GW Luo, YB Malureanu, CI Mawhinney, RD Parsons, J Sexton, JC Sui, CZ Vranas, PM AF Chen, D Chen, P Christ, NH Edwards, RG Fleming, GR Gaza, A Hansen, S Jung, C Kaehler, AL Kennedy, AD Kilcup, GW Luo, YB Malureanu, CI Mawhinney, RD Parsons, J Sexton, JC Sui, CZ Vranas, PM CA QCDSP Collaboration TI QCDSP - A status report SO NUCLEAR PHYSICS B-PROCEEDINGS SUPPLEMENTS LA English DT Article; Proceedings Paper CT XVth International Symposium on Lattice Field Theory (Lattice 97) CY JUL 22-26, 1997 CL EDINBURGH, SCOTLAND SP Cray Res, Silicon Graph, Hitachi, Inst Phys, UK Particle Phys & Astron Res Council, Univ Edinburgh AB The QCDSP machine at Columbia University has grown to 2,048 nodes achieving a peak speed of 100 Gigaflops. Software for quenched and Hybrid Monte Carlo (HMC) evolution schemes has been developed for staggered fermions, with support for Wilson and clover fermions under development. We provide an overview of the runtime environment, the current status of the QCDSP construction program and preliminary results not presented elsewhere in these proceedings. C1 Columbia Univ, New York, NY 10027 USA. Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Columbia Univ, Nevis Labs, Irvington, NY USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Dublin Trinity Coll, Dublin 2, Ireland. RP MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA. EM chen@ctp.mit.edu; pchen@cuphyb.phys.columbia.edu; nhc@phys.columbia.edu; edwards@scri.fsu.edu; gfleming@phys.columbia.edu; chulwoo@phys.columbia.edu; adrian@cuphyb.phys.columbia.edu; kilcup@physics.ohio-state.edu; roy@cuphyc.phys.columbia.edu; rdm@phys.columbia.edu; sexton@maths.tcd.ie; sui@cuphyc.phys.columbia.edu; vranas@phys.columbia.edu RI Fleming, George/L-6614-2013; OI Fleming, George/0000-0002-4987-7167; Vranas, Pavlos/0000-0002-8497-6283 NR 4 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0920-5632 EI 1873-3832 J9 NUCL PHYS B-PROC SUP JI Nucl. Phys. B-Proc. Suppl. PD APR PY 1998 VL 63 BP 997 EP 999 DI 10.1016/S0920-5632(97)00967-5 PG 3 WC Physics, Particles & Fields SC Physics GA ZG230 UT WOS:000072980200277 ER PT J AU Pitts, M Rahnema, F Williamson, TG Trumble, F AF Pitts, M Rahnema, F Williamson, TG Trumble, F TI Description of critical experiments in spherical geometry containing UO2F2 solution SO NUCLEAR TECHNOLOGY LA English DT Article DE highly enriched uranium; experiments; benchmark AB Hundreds of criticality experiments were performed at Oak Ridge National Laboratory in the 1950s. Several sets of these experiments were used to determine the critical properties of U-233 and U-235. Here, four sets are analyzed to provide benchmark descriptions for validation of computational tools used by nuclear criticality specialists, All four sets were performed in water-reflected spherical geometry and contained a highly enriched uranyl fluoride solution (93.18% U-235) With the hydrogen-to-fissile ratio of measurements ranging from 35.8 to 1272. The scope of these experiments spans the minimum values of the subcritical mass limit curve, One experiment was never reported in the open literature, and three experiments were performed at elevated temperatures. An uncertainty in the experimental k(eff) was found by sensitivity studies on reported measurement uncertainties, inconsistencies, and omissions in experimental parameters. To be useful for all computer codes, one-dimensional benchmark configurations were determined for all sets of experiments, The descriptions can be used to find bias values for a code/cross-section package, The k(eff) values for similar configurations can then be corrected using the bias values, The sensitivity analysis of the experiments was performed using ONEDANT with 27-group ENDF/B-IV cross sections and MCNP with continuous-energy ENDF/B-V cross-section data. The k(eff) values for both one-and three-dimensional configurations were found using MCNP with ENDF/B-V and ENDF/B-VI cross-section data, The values for k(eff) for the one-dimensional configuration were also found by using ONEDANT and KENO V.a with Hansen-Roach and 27-group ENDF/B-IV cross sections. C1 Georgia Inst Technol, George W Woodruff Sch Mech Engn, Nucl Engn Program, Atlanta, GA 30332 USA. Georgia Inst Technol, George W Woodruff Sch Mech Engn, Hlth Phys Program, Atlanta, GA 30332 USA. Westinghouse Savannah River Co, Savannah River Lab, Aiken, SC 29808 USA. RP Pitts, M (reprint author), Georgia Inst Technol, George W Woodruff Sch Mech Engn, Nucl Engn Program, Atlanta, GA 30332 USA. NR 19 TC 2 Z9 2 U1 1 U2 3 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD APR PY 1998 VL 122 IS 1 BP 1 EP 18 PG 18 WC Nuclear Science & Technology SC Nuclear Science & Technology GA ZD189 UT WOS:000072660300001 ER PT J AU Chang, GS AF Chang, GS TI Neutronic and burnup characteristics of an actinide-reduced plutonium fuel with tungsten SO NUCLEAR TECHNOLOGY LA English DT Article DE plutonium disposition; nonfertile tungsten; actinide-reduced fuel AB The United States and Russia expect to have a surplus of similar to 150 tonnes of weapons-grade plutonium (WGP) and 1000 tonnes of weapons-grade uranium resulting from drastic reductions in nuclear weapons programs. One of the most favored candidate methods for disposing of the WGP is to blend it with natural or depleted uranium down to 5 to 7 wt% of WGP for light water reactor (LWR) fuel pellet fabrication. However this approach, with a conversion ratio of 0.6, will produce more plutonium and other actinides in the spent fuel than the nonfertile fuel and the proposed actinide-reduced plutonium fuel (ARPF). This process only transforms the weapons-grade fissile materials to civilian-grade plutonium, which is still a nonproliferation concern, so it does not completely solve the plutonium disposition problem. Disposition of WGP in reactors without fertile material has been proposed by industry and national laboratories. A new ARPF is described that would use WGP mixed with medium-enrichment (20 at.% < U-235 < 93 at.%) UO2 and the nonfertile material tungsten to achieve a conversion ratio <0.1. The ARPF can meet the WGP disposal goal while minimizing the plutonium production. Its physics and burnup characteristics are analyzed, and the results are compared with LWR UO2 and mixed-oxide fuel. C1 Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Chang, GS (reprint author), Lockheed Martin Idaho Technol Co, Idaho Natl Engn & Environm Lab, POB 1625, Idaho Falls, ID 83415 USA. NR 15 TC 2 Z9 2 U1 0 U2 0 PU AMER NUCLEAR SOCIETY PI LA GRANGE PK PA 555 N KENSINGTON AVENUE, LA GRANGE PK, IL 60525 USA SN 0029-5450 J9 NUCL TECHNOL JI Nucl. Technol. PD APR PY 1998 VL 122 IS 1 BP 43 EP 51 PG 9 WC Nuclear Science & Technology SC Nuclear Science & Technology GA ZD189 UT WOS:000072660300003 ER PT J AU King, J Fairley, C Morgan, W AF King, J Fairley, C Morgan, W TI The joining of blunt DNA ends to 3 '-protruding single strands in Escherichia coli SO NUCLEIC ACIDS RESEARCH LA English DT Article ID NONHOMOLOGOUS RECOMBINATION; ILLEGITIMATE RECOMBINATION; CHROMOSOMAL INSTABILITY; TRANSFECTED DNA; MAMMALIAN-CELLS; POLYMERASE-I; BREAKS; GENE; DAMAGE; INTEGRATION AB In eukaryotic and prokaryotic organisms DNA double-strand breaks with non-complementary ends can be joined by mechanisms of illegitimate recombination. We examined the joining of 3'-protruding single strand (PSS) ends, which do not have recessed 3' hydroxyls that can allow for fill-in DNA synthesis, to blunt ends. End-joining was examined by electro-transforming Escherichia coli strains with linearized plasmid DNA, sequencing the resulting junctions, and determining the transformation frequencies. Three different E.coli strains were examined: MC1061, which has no known recombination or DNA repair defects, HB101 (recA(-)) and SURE (recB(-) recJ(-)). No striking differences were found in either the spectrum of products observed or the efficiency of end-joining between these strains. As in vertebrate systems, the majority of the products were overlaps between directly repeated DNA sequences. 3'-PSS are frequently preserved in vertebrate systems, but they were not preserved in our experiments unless the transforming DNA was pretreated with a DNA polymerase. C1 Univ Calif San Francisco, Dept Radiat Oncol, San Francisco, CA 94143 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. RP King, J (reprint author), Acacia Biosci Inc, 4136 Lakeside Dr, Richmond, CA 94806 USA. FU NIGMS NIH HHS [GM 53918] NR 37 TC 6 Z9 6 U1 0 U2 1 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD APR 1 PY 1998 VL 26 IS 7 BP 1749 EP 1754 DI 10.1093/nar/26.7.1749 PG 6 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZH038 UT WOS:000073065900026 PM 9512548 ER PT J AU Carr, GL Dumas, P Hirschmugl, CJ Williams, GP AF Carr, GL Dumas, P Hirschmugl, CJ Williams, GP TI Infrared synchrotron radiation programs at the National Synchrotron Light Source SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS LA English DT Article; Proceedings Paper CT 3rd Workshop on Development of Infrared Synchrotron Radiation and Applications to Materials Science CY MAR 27-28, 1997 CL ORSAY, FRANCE ID SPECTROSCOPY AB We review the properties of infrared synchrotron radiation and particularly those of the beamlines at the NSLS, Brookhaven National Laboratory. We show how this unique, pulsed broadband source with its 1000-fold brightness advantage over thermal sources has been utilized for research programs in surface science, solid-state physics and microscopy and discuss plans for 5 new beamlines at the NSLS. C1 Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Adv Light Source, Berkeley, CA 94720 USA. Univ Paris Sud, LURE, F-91405 Orsay, France. RP Carr, GL (reprint author), Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. NR 16 TC 48 Z9 49 U1 0 U2 1 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 0392-6737 J9 NUOVO CIMENTO D JI Nuovo Cimento Soc. Ital. Fis. D-Condens. Matter At. Mol. Chem. Phys. Fluids Plasmas Biophys. PD APR PY 1998 VL 20 IS 4 BP 375 EP 395 PG 21 WC Physics, Multidisciplinary SC Physics GA 104EM UT WOS:000075001800001 ER PT J AU Kincaid, BM AF Kincaid, BM TI Long-wavelength end-effect undulator radiation (transition undulator radiation) SO NUOVO CIMENTO DELLA SOCIETA ITALIANA DI FISICA D-CONDENSED MATTER ATOMIC MOLECULAR AND CHEMICAL PHYSICS FLUIDS PLASMAS BIOPHYSICS LA English DT Article; Proceedings Paper CT 3rd Workshop on Development of Infrared Synchrotron Radiation and Applications to Materials Science CY MAR 27-28, 1997 CL ORSAY, FRANCE AB As first pointed out by K.-J. Kim (KIM K.-J., Phys. Rev. Lett., 76 (1996) 1244) undulator radiation contains a broad-band component in the long-wavelength region. This radiation is due to the change in longitudinal velocity of an electron upon entering and leaving an undulator. The radiation pattern is a hollow cone, peaked in the forward direction, with an opening angle of approximately 1/gamma, with a spectrum covering a wide range, including the infra-red and the visible. The radiation is radially polarized, analogous to transition radiation, and exhibits interference effects between the entrance and exit ends of the undulator, similar to the interference effects observed for transition radiation from a thin slab of material. A straightforward application of formulas from Jackson (JACKSON J. D., Classical Electrodynamics, 2nd edition (J. Wiley & Sons, N.Y.) 1975) results in a closed-form exact expression for the low-frequency limit of this novel radiation effect, Transition Undulator Radiation or TUR. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Kincaid, BM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 11 TC 5 Z9 5 U1 0 U2 0 PU EDITRICE COMPOSITORI BOLOGNA PI BOLOGNA PA VIA STALINGRADO 97/2, I-40128 BOLOGNA, ITALY SN 0392-6737 J9 NUOVO CIMENTO D JI Nuovo Cimento Soc. Ital. Fis. D-Condens. Matter At. Mol. Chem. Phys. Fluids Plasmas Biophys. PD APR PY 1998 VL 20 IS 4 BP 495 EP 502 PG 8 WC Physics, Multidisciplinary SC Physics GA 104EM UT WOS:000075001800008 ER PT J AU Ning, CZ Bischoff, S Koch, SW Harkness, GK Moloney, JV Chow, WW AF Ning, CZ Bischoff, S Koch, SW Harkness, GK Moloney, JV Chow, WW TI Microscopic modeling of vertical-cavity surface-emitting lasers: many-body interaction, plasma heating, and transverse dynamics SO OPTICAL ENGINEERING LA English DT Article DE bloch equations; vertical-cavity surface-emitting lasers (VCSELs); plasma heating; mode dynamics ID SEMICONDUCTOR MICROCAVITY LASERS; GAIN; AMPLIFIERS; MODES AB A microscopic theory for the interaction between semiconductor quantum-well structures and laser fields based on the semiconductor Bloch equations is applied to vertical-cavity surface-emitting lasers (VCSELs) with the inclusion of plasma heating. The semiconductor Bloch equations are reduced to a set of equations for the first and second moments of the carrier distribution functions. Plasma heating and many-body effects are then studied by solving this set of equations in steady state under the approximation of a single transverse and longitudinal mode. The transverse-and longitudinal-mode dynamics of VCSELs is analyzed by solving the full space-time-dependent problem. (C) 1998 Society of Photo-Optical instrumentation Engineers. C1 NASA, Ames Res Ctr, Moffett Field, CA 94035 USA. Univ Marburg, Fachbereich Phys, D-35032 Marburg, Germany. Univ Marburg, Zentrum Mat Wissensch, D-35032 Marburg, Germany. Univ Arizona, Arizona Ctr Math Sci, Tucson, AZ 85721 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ning, CZ (reprint author), NASA, Ames Res Ctr, Mail Stop T27A-1, Moffett Field, CA 94035 USA. RI Ning, C. Z./D-4699-2009 OI Ning, C. Z./0000-0003-4583-8889 NR 22 TC 5 Z9 5 U1 0 U2 0 PU SPIE - INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING PI BELLINGHAM PA POB 10, BELLINGHAM, WA 98227-0010 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 1998 VL 37 IS 4 BP 1175 EP 1181 DI 10.1117/1.602032 PG 7 WC Optics SC Optics GA ZG374 UT WOS:000072995200015 ER PT J AU Naday, I Ross, S Westbrook, EM Zentai, G AF Naday, I Ross, S Westbrook, EM Zentai, G TI Charge-coupled device fiber optic taper array x-ray detector for protein crystallography SO OPTICAL ENGINEERING LA English DT Article DE charge-coupled device; fiber optic taper; x-ray diffraction; crystallography; imaging detector ID AREA DETECTOR; DESIGN AB A large area charge-coupled device (CCD) based fiber optic taper array detector (APS-1) is installed at the insertion-device beamline of the Structural Biology Center at the Argonne Advanced Photon Source x-ray synchrotron. The detector is used in protein crystallography diffraction experiments, where the objective is to measure the position and intensity of x-ray Bragg peaks in diffraction images. Large imaging area, very high spatial resolution, high x-ray sensitivity, good detective quantum efficiency, low noise, wide dynamic range, excellent stability and short readout time are all fundamental requirements in this application. The APS-1 detector converts the 2-D x-ray patterns to visible light images by a thin layer of x-ray sensitive phosphor. The phosphor coating is directly deposited on the large ends of nine fiber optic tapers arranged in a 3x3 array. Nine, thermoelectrically cooled 1024x1024 pixel CCDs image the patterns, demagnified by the tapers. After geometrical and uniformity corrections, the nine areas give a continuous image of the detector face with virtually no gaps between the individual tapers. The 18 parallel analog signal-processing channels and analog-to-digital converters ensure short readout time and low readout noise. We discuss the design and measured performance of the detector. (C) 1998 Society of Photo-Optical Instrumentation Engineers. C1 Argonne Natl Lab, Argonne, IL 60439 USA. RP Naday, I (reprint author), Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 18 Z9 19 U1 1 U2 3 PU SPIE - INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING PI BELLINGHAM PA POB 10, BELLINGHAM, WA 98227-0010 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 1998 VL 37 IS 4 BP 1235 EP 1244 DI 10.1117/1.601789 PG 10 WC Optics SC Optics GA ZG374 UT WOS:000072995200024 ER PT J AU Descour, MR Sweatt, WC Krenz, KD AF Descour, MR Sweatt, WC Krenz, KD TI Mass-producible microtags for security applications: calculated fabrication tolerances by vigorous coupled-wave analysis SO OPTICAL ENGINEERING LA English DT Article DE computer-generated holograms; security and anticounterfeiting devices; grating fabrication tolerances; rigorous coupled-wave analysis ID EFFICIENT IMPLEMENTATION; TM POLARIZATION; GRATINGS; CONVERGENCE AB We develop a method for encoding phase and amplitude in microscopic computer-generated holograms (microtags) for security applications. An 8x8 cell phase-only and an 8x8 cell phase-and-amplitude microtag design are fabricated in photoresist using an extreme ultraviolet (13.4-nm) lithography (EUVL) tool. Each microtag measures 80x 160 mu m and contains features 0.2 mu m wide. Fraunhofer-zone diffraction patterns can be obtained from fabricated microtags without any intervening optics and compare very favorably with predicted diffraction patterns [Descour et al. (1996)]. We present the results of a rigorous coupled-wave analysis (RCWA) of microtags. Microtags are modeled as consisting of subwavelength gratings of a trapezoidal profile. Transverse-electric (TE) and TM readout polarizations are modeled. The analysis concerns the determination of optimal microtag-grating design parameter values and tolerances on those parameters. The parameters are grating wall-slope angle, grating duty cycle, grating depth, and metal coating thickness. Optimal microtag-grating parameter values result in maximum diffraction efficiency, which is calculated at 16% for microtag gratings in air and 12% for microtag gratings underneath a protective dielectric coating, within fabrication constraints. TM-polarized readout illumination is diffracted with higher efficiency than TE-polarized illumination by microtag gratings. (C) 1998 Society of Photo-Optical Instrumentation Engineers. C1 Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. Sandia Natl Labs, Livermore, CA 94550 USA. RP Descour, MR (reprint author), Univ Arizona, Ctr Opt Sci, Tucson, AZ 85721 USA. EM michael.descour@opt-sci.arizona.edu NR 16 TC 1 Z9 1 U1 0 U2 1 PU SPIE - INTERNATIONAL SOCIETY FOR OPTICAL ENGINEERING PI BELLINGHAM PA POB 10, BELLINGHAM, WA 98227-0010 USA SN 0091-3286 J9 OPT ENG JI Opt. Eng. PD APR PY 1998 VL 37 IS 4 BP 1254 EP 1261 DI 10.1117/1.601961 PG 8 WC Optics SC Optics GA ZG374 UT WOS:000072995200027 ER PT J AU Richman, BA Bisson, SE Trebino, R Sidick, E Jacobson, A AF Richman, BA Bisson, SE Trebino, R Sidick, E Jacobson, A TI Efficient broadband second-harmonic generation by dispersive achromatic nonlinear conversion using only prisms SO OPTICS LETTERS LA English DT Article ID FEMTOSECOND PULSES AB Using a lossless dispersive apparatus consisting of six prisms, optimized to match a second-harmonic crystal phase-matching angle versus wavelength to second order, we efficiently doubled tunable fundamental light near 660 nm over a range of 80 nm, using a 4-mm-long type I beta-barium berate crystal without tuning the crystal angle. Another set of six prisms after the crystal realigned the propagation directions of the various second-harmonic frequencies to be collinear to within 1/4 spot diameter in position and 200 mu rad in angle. The measured conversion efficiency of a 40-mJ, 5-ns fundamental pulse was 10%. (C) 1998 Optical Society of America. C1 Sandia Natl Labs, Combust Res Facil, Livermore, CA 94551 USA. CVI Laser Corp, Livermore, CA 94550 USA. RP Richman, BA (reprint author), Sandia Natl Labs, Combust Res Facil, M-S 9051, Livermore, CA 94551 USA. NR 8 TC 31 Z9 31 U1 0 U2 1 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 0146-9592 J9 OPT LETT JI Opt. Lett. PD APR 1 PY 1998 VL 23 IS 7 BP 497 EP 499 DI 10.1364/OL.23.000497 PG 3 WC Optics SC Optics GA ZF079 UT WOS:000072860500005 PM 18084555 ER PT J AU Shoari, S Bagherzadeh, N Goodman, D Milner, TE Smithies, DJ Nelson, JS AF Shoari, S Bagherzadeh, N Goodman, D Milner, TE Smithies, DJ Nelson, JS TI A parallel algorithm for pulsed laser infrared tomography SO PATTERN RECOGNITION LETTERS LA English DT Article DE parallel processing; system performance; conjugate gradient algorithm; infrared image AB A three-dimensional Tomographic Reconstruction Algorithm (3D TRA) has been developed and implemented on a parallel machine at the Maul High Performance Computing Center (MHPCC). Given a time sequence of infrared images, this algorithm provides information to determine the location, physical dimensions, and initial space-dependent temperature increase of laser heated blood vessels. In this approach the serial computation of a 3D TRA is decomposed into multiple tasks which can be executed in parallel to reduce the computation time. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Irvine, Dept Elect & Comp Engn, Irvine, CA 92697 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Irvine, Beckman Laser Inst & Med Clin, Irvine, CA 92697 USA. RP Bagherzadeh, N (reprint author), Univ Calif Irvine, Dept Elect & Comp Engn, Irvine, CA 92697 USA. NR 5 TC 0 Z9 0 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0167-8655 J9 PATTERN RECOGN LETT JI Pattern Recognit. Lett. PD APR PY 1998 VL 19 IS 5-6 BP 521 EP 526 DI 10.1016/S0167-8655(98)00029-4 PG 6 WC Computer Science, Artificial Intelligence SC Computer Science GA 105CD UT WOS:000075054100017 ER PT J AU Chu, F Lu, YC Kotula, PG Mitchell, TE Thoma, DJ AF Chu, F Lu, YC Kotula, PG Mitchell, TE Thoma, DJ TI Phase stability and defect structure of the C15 phase in the Hf-V-Nb system SO PHILOSOPHICAL MAGAZINE A-PHYSICS OF CONDENSED MATTER STRUCTURE DEFECTS AND MECHANICAL PROPERTIES LA English DT Article ID LAVES-PHASE; ELASTIC PROPERTIES; MECHANICAL-PROPERTIES; ELECTRONIC-STRUCTURE; ALLOYS; SUPERCONDUCTORS; INTERMETALLICS; DEFORMATION; ELEMENTS; CR2NB AB The phase stability and defect structure in the C15 HfV2-based Laves phase were studied by a combined experimental and theoretical investigation. It was found that C15 HfV2 can be alloyed with a large amount of Nb (about 20 at.%), where the Nb atoms occupy both I-If and V sites, and the lattice parameters of the ternary C15 phases containing the same Nb content decrease with increasing V to Hf ratio. The extended defects observed in the ternary C15 phase are extrinsic {111} stacking faults, {111}[112] annealing twins, and faceted Sigma = 3 ([111], 70.53 degrees) grain boundaries. Examination of the extrinsic {111} stacking faults revealed that synchroshear may occur in this C15 phase. The total and l-projected density of electronic states of C15 HfV2 were obtained by first-principles total energy and electronic structure calculations. The phase stability, Nb site occupancy and compositional dependence of the lattice parameter of the C15 phase in the Hf-V-Nb system are qualitatively explained by geometric and electronic structure considerations. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Chu, F (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS K765, Los Alamos, NM 87545 USA. RI Kotula, Paul/A-7657-2011 OI Kotula, Paul/0000-0002-7521-2759 NR 39 TC 14 Z9 15 U1 0 U2 3 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0141-8610 J9 PHILOS MAG A JI Philos. Mag. A-Phys. Condens. Matter Struct. Defect Mech. Prop. PD APR PY 1998 VL 77 IS 4 BP 941 EP 956 PG 16 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering; Physics, Applied; Physics, Condensed Matter SC Materials Science; Metallurgy & Metallurgical Engineering; Physics GA ZD850 UT WOS:000072730700008 ER PT J AU Wei, W Schwartz, J Goretta, KC Balachandran, U Bhargava, A AF Wei, W Schwartz, J Goretta, KC Balachandran, U Bhargava, A TI Effects of nanosize MgO additions to bulk Bi2.1Sr1.7CaCu2Ox SO PHYSICA C LA English DT Article DE Bi-2212; nanosize MgO; flux pinning ID CRITICAL-CURRENT-DENSITY; FLUX; TAPES; BI2SR2CACU2OX; CRYSTALS; ZIRCONIA; DEFECTS; CARBON; WIRES; LINE AB Nanosize MgO particles were added to Bi2.1Sr1.7CaCu2Ox (Bi-2212) powder in various molar fractions. Bulk samples were made from the MgO/Bi-2212 and heat treated by partial-melt processing. Scanning electron microscopy and energy-dispersive X-ray spectra were used to study the phases present in the samples. The effects of the MgO additions on the flux pinning behavior as a function of magnetic field and temperature were investigated by magnetization hysteresis measurements obtained with a SQUID magnetometer and a 33 T vibrating sample magnetometer. It was found that the nanosize MgO addition did not affect T-c of Bi-2212, while significantly expanding the magnetization hysteresis loops and increasing the irreversibility field. X-ray and SEM analysis suggested that MgO is inert with respect to Bi-2212. (C) 1998 Elsevier Science B.V. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. FSU, FAMU, Coll Engn, Dept Mech Engn, Tallahassee, FL 32310 USA. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. Univ Queensland, Brisbane, Qld 4072, Australia. RP Wei, W (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32310 USA. RI Schwartz, Justin/D-4124-2009 OI Schwartz, Justin/0000-0002-7590-240X NR 30 TC 37 Z9 38 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD APR 1 PY 1998 VL 298 IS 3-4 BP 279 EP 288 DI 10.1016/S0921-4534(97)01889-3 PG 10 WC Physics, Applied SC Physics GA ZN320 UT WOS:000073634100015 ER PT J AU Bill, A Wolf, SA Ovchinnikov, YN Kresin, VZ AF Bill, A Wolf, SA Ovchinnikov, YN Kresin, VZ TI Effect of magnetic impurity correlations on Josephson tunneling SO PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS LA English DT Article DE Josephson effect; pair breaking ID SR-CU-O; CRITICAL-FIELD; NORMAL-STATE; SUPERCONDUCTORS; TEMPERATURE; DEPENDENCE AB The ordering trend of magnetic impurities at low temperature results in the frustration of the pair-breaking effect and induces a 'recovery' of superconducting properties. We show that this effect manifests itself in the deviation of the Josephson current amplitude from the values obtained within the Ambegaokar-Baratoff and the Abrikosov-Gor'kov models. We consider both weak and strong-coupling cases. The theory is applied to describe the experimental data obtained for the low-T-c superconductor SmRh4B4. We further predict a 'recovery' effect of the Josephson current in high-temperature superconductors. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. USN, Res Lab, Washington, DC 20375 USA. Russian Acad Sci, LD Landau Inst Theoret Phys, Moscow 11733V, Russia. RP Univ Calif Berkeley, Lawrence Berkeley Lab, MS 62-203,1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Wolf, Stuart/A-7513-2009 NR 27 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 EI 1873-2143 J9 PHYSICA C JI Physica C PD APR 1 PY 1998 VL 298 IS 3-4 BP 231 EP 239 DI 10.1016/S0921-4534(97)01813-3 PG 9 WC Physics, Applied SC Physics GA ZN320 UT WOS:000073634100010 ER PT J AU Pindzola, MS Mitnik, DM Shaw, JA Griffin, DC Badnell, NR Summers, HP Schultz, DR AF Pindzola, MS Mitnik, DM Shaw, JA Griffin, DC Badnell, NR Summers, HP Schultz, DR TI Electron-impact ionization of atomic ions in the Na isoelectronic sequence SO PHYSICA SCRIPTA LA English DT Article ID COMPLEX SPECTRA; AUTOIONIZATION; EXCITATION AB A database is assembled which contains electron-impact ionization rate coefficients for selected atomic ions in the Na isoelectronic sequence. The rate coefficients are obtained from a Maxwellian convolution of distorted-wave cross sections which include direct ionization of the 2p and 3s subshells, as well as inner-shell excitations from the 2s and 2p subshells leading to autoionization. These excitation-autoionization contributions can be large for many Na-like atomic ions. To assist modeling efforts of moderately dense plasmas, the rate coefficients are resolved as to the final state of the ionization process. A sample database we is presented for Fe15+. The complete database will reside in electronic form at the Controlled Fusion Atomic Data Center at ORNL (http://www-cfadc.phy.ornl.gov/data_and_codes/). C1 Auburn Univ, Dept Phys, Auburn, AL 36849 USA. Rollins Coll, Dept Phys, Winter Pk, FL 32789 USA. Univ Strathclyde, Dept Phys & Appl Phys, Glasgow G4 0NG, Lanark, Scotland. Oak Ridge Natl Lab, Div Phys, Controlled Fus Atom Data Ctr, Oak Ridge, TN 37831 USA. RP Pindzola, MS (reprint author), Auburn Univ, Dept Phys, Auburn, AL 36849 USA. NR 16 TC 7 Z9 7 U1 0 U2 0 PU ROYAL SWEDISH ACAD SCIENCES PI STOCKHOLM PA PUBL DEPT BOX 50005, S-104 05 STOCKHOLM, SWEDEN SN 0281-1847 J9 PHYS SCRIPTA JI Phys. Scr. PD APR PY 1998 VL 57 IS 4 BP 514 EP 518 DI 10.1088/0031-8949/57/4/008 PG 5 WC Physics, Multidisciplinary SC Physics GA ZG752 UT WOS:000073035800008 ER PT J AU Buttler, WT Hughes, RJ Kwiat, PG Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM AF Buttler, WT Hughes, RJ Kwiat, PG Luther, GG Morgan, GL Nordholt, JE Peterson, CG Simmons, CM TI Free-space quantum-key distribution SO PHYSICAL REVIEW A LA English DT Article ID OPTICAL-FIBER; CRYPTOGRAPHY; PHOTONS; CANNOT; ALWAYS; LIGHT; LONG AB A working free-space quantum key distribution (QKD) system has been developed and tested over a 205-m indoor optical path at Los Alamos National Laboratory under fluorescent lighting conditions. Results show that free-space QKD can provide a secure real-time key distribution between parties who have a need to communicate secretly. C1 Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. RP Buttler, WT (reprint author), Los Alamos Natl Lab, Div Phys, POB 1663, Los Alamos, NM 87545 USA. NR 23 TC 44 Z9 51 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 EI 1094-1622 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2379 EP 2382 DI 10.1103/PhysRevA.57.2379 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700019 ER PT J AU Miyano, KE Arp, U Southworth, SH Meehan, TE Walsh, TR Larkins, FP AF Miyano, KE Arp, U Southworth, SH Meehan, TE Walsh, TR Larkins, FP TI Sulfur K beta x-ray emission from carbonyl sulfide: Variations with polarization and excitation energy at the S K threshold SO PHYSICAL REVIEW A LA English DT Article ID AB-INITIO CALCULATIONS; GAUSSIAN BASIS FUNCTIONS; FIRST-ROW ATOMS; MOLECULAR CALCULATIONS; N2O MOLECULE; SPECTRA; ANISOTROPY AB Sulfur K beta x-ray-emission spectra from carbonyl sulfide have been measured with resonant excitation at the sulfur K absorption threshold and compared with results of self-consistent field and singles-doubles configuration-interaction calculations. For excitation to the strong 4 pi absorption resonance, a splitting of the main emission peak is interpreted in terms of influence of the 4 pi electron on the final valence-hole states. The polarization selectivity of the emission spectrometer was used to distinguish emission polarized parallel versus perpendicular with respect to the polarization of the excitation radiation. The observed polarization dependence is consistent with the molecular symmetries of the calculated intermediate and final states. C1 CUNY Brooklyn Coll, Dept Phys, Brooklyn, NY 11210 USA. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Univ Melbourne, Sch Chem, Parkville, Vic 3052, Australia. RP Miyano, KE (reprint author), CUNY Brooklyn Coll, Dept Phys, Brooklyn, NY 11210 USA. RI Walsh, Tiffany/C-2667-2009; Arp, Uwe/C-2854-2009; OI Walsh, Tiffany/0000-0002-0233-9484; Arp, Uwe/0000-0002-6468-9455 NR 28 TC 6 Z9 6 U1 0 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2430 EP 2435 DI 10.1103/PhysRevA.57.2430 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700026 ER PT J AU Hansen, DL Arrasate, ME Cotter, J Fisher, GR Leung, KT Levin, JC Martin, R Neill, P Perera, RCC Sellin, IA Simon, M Uehara, Y Vanderford, B Whitfield, SB Lindle, DW AF Hansen, DL Arrasate, ME Cotter, J Fisher, GR Leung, KT Levin, JC Martin, R Neill, P Perera, RCC Sellin, IA Simon, M Uehara, Y Vanderford, B Whitfield, SB Lindle, DW TI Neutral dissociation of hydrogen following photoexcitation of HCl at the chlorine K edge SO PHYSICAL REVIEW A LA English DT Article ID SYNCHROTRON RADIATION BEAMLINE; HIGH-ENERGY-RESOLUTION; ADVANCED LIGHT-SOURCE; RESONANT AUGER DECAY; X-RAY SPECTROSCOPY; COINCIDENCE MEASUREMENTS; COMPETITION; PERFORMANCE; MOLECULES; STATES AB Time-of-flight mass spectroscopy was used to study the relaxation dynamics of HCl following photoexcitation in the vicinity of the Cl K edge (similar to 2.8 keV) using monochromatic synchrotron radiation. At the lowest resonant excitation to the 6 sigma* antibonding orbital, almost half of the excited molecules decay by emission of a neutral H atom, mostly in coincidence with a highly charged Cln+ ion. The present work demonstrates that neutral-atom emission can be a significant decay channel for excited states with very short lifetimes (1 fs). C1 Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. Univ Nevada, Dept Phys, Reno, NV 89557 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Waterloo, Dept Chem, Waterloo, ON N2L 3G1, Canada. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Univ Paris Sud, LURE, F-91405 Orsay, France. CENS, CEA, DRECAM, SPAM, F-91191 Gif Sur Yvette, France. Mitsubishi Elect Co, Amagasaki, Hyogo 661, Japan. Univ Wisconsin, Dept Phys & Astron, Eau Claire, WI 54702 USA. RP Hansen, DL (reprint author), Univ Nevada, Dept Chem, Las Vegas, NV 89154 USA. NR 16 TC 24 Z9 24 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2608 EP 2611 DI 10.1103/PhysRevA.57.2608 PG 4 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700049 ER PT J AU Cohen, M Fournier, KB Goldstein, WH AF Cohen, M Fournier, KB Goldstein, WH TI Excitation autoionization rates from ground and excited levels in Li-like Ar15+ to S-like Ar2+ SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON-IMPACT IONIZATION; SODIUM-LIKE IONS; NA-LIKE IONS; CROSS-SECTIONS; CONFIGURATION-INTERACTION; RATE COEFFICIENTS; AUTO-IONIZATION; COMPLEX SPECTRA; CU-LIKE; AR-7+ AB The rate coefficients for excitation autoionization (EA) from the levels of the ground and first excited configuration in nearly all argon ions (Li-like Ar15+ to S-like Ar2+) have been computed. Collisional excitation cross sections are computed in the distorted-wave approximation and integrated over a Maxwellian distribution of free-electron energies. Radiative and autoionizing transition probabilities are computed using the fully relativistic, intermediate coupling code RELAC. For each ion, the rates df EA are compared to semi-empirical calculations of the direct ionization rate. For charge states with few M-shell electrons in the ground configuration (Na-, Mg-, and Al-like), EA can significantly enhance the direct ionization rate coefficients. In the first excited configuration of each ion considered, the EA rate coefficient enhances the direct ionization rate coefficient only at low temperatures. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Cohen, M (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 34 TC 2 Z9 2 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2651 EP 2671 DI 10.1103/PhysRevA.57.2651 PG 21 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700055 ER PT J AU Woitke, O Zavodszky, PA Ferguson, SM Houck, JH Tanis, JA AF Woitke, O Zavodszky, PA Ferguson, SM Houck, JH Tanis, JA TI Target ionization and projectile charge changing in 0.5-8-MeV/q Liq++He (q=1,2,3) collisions SO PHYSICAL REVIEW A LA English DT Article ID ELECTRON LOSS; SIMULTANEOUS CAPTURE; HELIUM; SINGLE; IONS; HE; PROTONS; AR AB Target ionization and projectile charge changing were investigated for 0.5-8-MeV/qLi(q+)+He (q = 1,2,3) collisions. Cross sections for the single and double ionization of He associated with no projectile charge change (direct ionization), single-electron capture, and single-electron loss were measured using coincidence techniques and compared to existing experimental and theoretical results. Total cross sections for single-electron capture (for Li-1,Li-2,Li-3+) and single-electron loss (for Li-1,Li-2+) mere also obtained. For a given incoming projectile charge state the double-to-single target ionization ratios R vary strongly with the outgoing reaction channel. For direct ionization, R is nearly independent of the incident projectile charge state and can be described by the semi-empirical scaling rule of Knudsen et al. [J. Phys. B 17, 3545 (1984)]. However, for ionization associated with single-electron loss and single-electron capture by the projectile, R depends quite strongly on the incident charge state of the projectile. These ionization ratios R are interpreted in terms of theoretical formulations involving electron-nucleus interactions and electron-electron interactions. C1 Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. RP Woitke, O (reprint author), Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. NR 19 TC 64 Z9 64 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2692 EP 2700 DI 10.1103/PhysRevA.57.2692 PG 9 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700058 ER PT J AU Minniti, R Elston, SB Reinhold, CO Lim, JY Burgdorfer, J AF Minniti, R Elston, SB Reinhold, CO Lim, JY Burgdorfer, J TI Measurements of absolute electron-emission spectra from grazing-incidence ion-surface collisions SO PHYSICAL REVIEW A LA English DT Article ID FAST HEAVY-IONS; CONVOY ELECTRONS; IMAGE-CHARGE; ACCELERATION; ANGLE; SCATTERING; CONTINUUM; CAPTURE AB Convoy electron spectra have been measured in coincidence with specularly reflected ions in grazing-incidence collisions of carbon ions with a silicon (100) surface. Absolute yields of convoy electrons have been determined experimentally and compared with the results obtained from a classical trajectory Monte Carlo simulation. By comparing the velocity dependence of the convoy yields with theory, we are able to assess the relative contribution to convoy emission from valence and core electron capture to continuum states of the projectile. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Minniti, R (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. OI Reinhold, Carlos/0000-0003-0100-4962 NR 27 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2731 EP 2736 DI 10.1103/PhysRevA.57.2731 PG 6 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700063 ER PT J AU Rosner, B Datz, S Wu, W Jones, NL Schultz, DR Reinhold, CO AF Rosner, B Datz, S Wu, W Jones, NL Schultz, DR Reinhold, CO TI Charge-state dependence of energy loss in random solids SO PHYSICAL REVIEW A LA English DT Article ID ION-ATOM COLLISIONS; BINARY PEAK; CARBON AB We measured the energy loss of 10-, 16-, and 25-MeV oxygen ions in a thin (7.5 mu g/cm(2)) carbon foil as a function of input charge state (q =4-8). At this thickness, charge-state equilibrium is nearly attained, but the energy losses accumulated over the ion's trajectory are a function of its initial charge state. Using a set of pertinent microscopic atomic collision-cross sections computed using the classical trajectory Monte Carlo method, we link these parameters to the observed charge-state-dependence on energy loss through a classical transport simulation. This simulation also leads to a prediction of charge-state equilibrium fractions. C1 Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. RP Rosner, B (reprint author), Technion Israel Inst Technol, Dept Phys, IL-32000 Haifa, Israel. OI Reinhold, Carlos/0000-0003-0100-4962 NR 17 TC 13 Z9 13 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2737 EP 2741 DI 10.1103/PhysRevA.57.2737 PG 5 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700064 ER PT J AU McGuire, EJ AF McGuire, EJ TI Bethe stopping-power formula for structured projectiles SO PHYSICAL REVIEW A LA English DT Article ID PARTIALLY STRIPPED IONS; AL; PROTONS; CU; AG; AU; APPROXIMATION; ALUMINUM; ENERGY AB It is known that the energy loss in ion-atom collisions is dominated by elastic scattering of one collision partner and excitation or ionization of the second. This is true for both structured and structureless projectiles. Here, I show that this fact leads to a relatively simple extension of the Bethe stopping-power formula for structureless projectiles to structured projectiles. The formula replaces the Bethe mean excitation energy with two other mean energies which reflect the elastic scattering factor of the otherwise structureless projectile. The expression is symmetrical in the center-of-mass system. The formula is in excellent agreement with numerical calculations, when the numerical calculations are asymptotic. To obtain the extended Bethe stopping formula, it is necessary to evaluate integrals over energy and momentum transfer involving generalized oscillator strengths, properly treating the energy-dependent lower Limit in the momentum transfer integral. I do this by a constructive procedure using two cutoffs (instead of the traditional one) in momentum transfer. Peek had earlier developed a procedure to address the question of whether the Bethe mean excitation energy calculated with optical oscillator strengths is the same as the Bethe mean excitation energy appearing in the stopping power formula. I show that the result of the constructive procedure agrees with the result of Peek in the asymptotic limit, and I develop a criterion to determine the asymptotic limit. C1 Sandia Natl Labs, Div 9571, Albuquerque, NM 87185 USA. RP McGuire, EJ (reprint author), Sandia Natl Labs, Div 9571, Albuquerque, NM 87185 USA. NR 19 TC 12 Z9 12 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1050-2947 J9 PHYS REV A JI Phys. Rev. A PD APR PY 1998 VL 57 IS 4 BP 2758 EP 2771 DI 10.1103/PhysRevA.57.2758 PG 14 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZJ698 UT WOS:000073243700067 ER PT J AU Heid, R Bohnen, KP Ho, KM AF Heid, R Bohnen, KP Ho, KM TI Ab initio phonon dynamics of rhodium from a generalized supercell approach SO PHYSICAL REVIEW B LA English DT Article ID GROUND-STATE PROPERTIES; TRANSITION-METALS; ABINITIO CALCULATION; DISPERSIONS AB We present a generalization of the supercell approach to the ab initio determination of the complete lattice dynamics. Combining force calculations for supercells of arbitrary shapes greatly increases the number of accessible interatomic force constants without the necessity to resort to large supercell sizes. The method allows a systematic a priori search for optimal supercell geometries as well as a posteriori improvements of calculations already performed. Its ability to efficiently handle systems with longer-range lattice interactions is demonstrated for the transition metal rhodium. The present approach has the potential to extend the applicability of the conceptually simple direct approach to the calculation of the complete phonon spectra for lattices with larger unit cells. C1 Max Planck Inst Phys Komplexer Syst, D-01187 Dresden, Germany. Forschungszentrum Karlsruhe, Inst Nukl Festkorperphys, D-76021 Karlsruhe, Germany. Iowa State Univ, Ames Lab, US Dept Energy, Ames, IA 50011 USA. Iowa State Univ, Dept Phys, Ames, IA 50011 USA. RP Heid, R (reprint author), Max Planck Inst Phys Komplexer Syst, Nothnitzer Str 38, D-01187 Dresden, Germany. NR 16 TC 15 Z9 15 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7407 EP 7410 DI 10.1103/PhysRevB.57.7407 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300002 ER PT J AU Martin, JM Lees, MR Paul, DM Dai, P Ritter, C Bi, YJ AF Martin, JM Lees, MR Paul, DM Dai, P Ritter, C Bi, YJ TI Neutron-diffraction study of CeCuGa3 SO PHYSICAL REVIEW B LA English DT Article ID ALLOYS AB Neutron-diffraction experiments have been performed on both polycrystalline and single-crystal samples of CeCuGa3. The results of the powder diffraction experiments show that CeCuGa3 adopts an incommensurate magnetic structure at 1.25 K. The propagation wave vector associated with the magnetic ordering k(m) is (0.176, 0.176, 0), and the magnitude of the magnetic moment in the ordered state is 1.24 +/- 0.02 mu(B). Single-crystal neutron diffraction confirmed the existence of magnetic satellite peaks at Q values determined by the wave vector k(m). Additional satellites have been observed in the single-crystal diffraction experiments with an incommensurate propagation vector of k(s) = (0.137, 0.137, 0). These are probably the result of a short-ranged modulation of the crystal structure. C1 Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble, France. Univ Birmingham, Sch Met & Mat, Birmingham B15 2TT, W Midlands, England. RP Martin, JM (reprint author), Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. RI Dai, Pengcheng /C-9171-2012; Lees, Martin/D-9584-2013 OI Dai, Pengcheng /0000-0002-6088-3170; Lees, Martin/0000-0002-2270-2295 NR 13 TC 5 Z9 5 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7419 EP 7422 DI 10.1103/PhysRevB.57.7419 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300005 ER PT J AU Wang, XD AF Wang, XD TI Theory of spin waves in a ferromagnetic Kondo lattice model SO PHYSICAL REVIEW B LA English DT Article ID DOUBLE-EXCHANGE AB A random-phase approximation theory for spin waves in a ferromagnetic Kondo lattice model is presented. In the strong-coupling limit, this theory agrees with the existing theoretical results, in which the magnetic coupling is taken to be infinite a priori. It is shown explicitly that, in the strong-coupling limit, the spin-wave spectrum of the system is identical to that of a short-range Heisenberg model for the case of a single conduction band with short-range hopping integrals. In the intermediate coupling regime, on the other hand, more complicated effects, such as softening or disappearance of spin waves, are likely to be observed. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Wang, XD (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 6 TC 27 Z9 27 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7427 EP 7430 DI 10.1103/PhysRevB.57.7427 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300007 ER PT J AU Graf, T Hundley, MF Modler, R Movshovich, R Thompson, JD Mandrus, D Fisher, RA Phillips, NE AF Graf, T Hundley, MF Modler, R Movshovich, R Thompson, JD Mandrus, D Fisher, RA Phillips, NE TI Magnetic phase transitions in CeRh2Si2: Specific heat, susceptibility, and resistance studies SO PHYSICAL REVIEW B LA English DT Article ID CERU2SI2; SUPERCONDUCTIVITY AB Two phase transitions near 35 and 24 K can be detected in the specific heat, susceptibility, and resistivity of CeRh2Si2. We interpret the 35 K transition as magnetic ordering in a (1/2 1/2 1/2) structure. The much weaker transition near 24 K corresponds to the development of domains having a (1/2 1/2 0) magnetic structure that grow spatially at the expense of the (1/2 1/2 1/2) structure. This interpretation of the magnetic phase diagram of CeRh2Si2 clarifies a controversy surrounding observations by neutron diffraction. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94270 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94270 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Graf, T (reprint author), ETH Zurich, CH-8093 Zurich, Switzerland. RI Mandrus, David/H-3090-2014 NR 23 TC 30 Z9 30 U1 3 U2 13 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7442 EP 7445 DI 10.1103/PhysRevB.57.7442 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300011 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI Coherent versus incoherent resonant tunneling in high-T-c cuprates SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL CONDUCTIVITY; AXIS CONDUCTIVITY; PSEUDOGAP; SUPERCONDUCTORS; YBA2CU3OX; STATE AB An analysis is performed of the resonant tunneling transport along the c axis in the case where the concentration of localized resonant centers is low and the tunneling via different centers becomes incoherent. In this case the planar component of the quasimomentum is not conserved in the process of interlayer hopping. For the normal conductivity, as function of temperature and frequency, this leads only to a change of a prefactor. However, the supercurrent along the c axis vanishes if the order parameter is of d type and the tunneling is incoherent. An interpolation is proposed, describing a partially coherent case, when the interference terms are suppressed, but still present. A rapid decrease of the critical temperature with concentration of resonant centers and the possibility of a d --> s phase transition are predicted. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 14 TC 9 Z9 9 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7488 EP 7490 DI 10.1103/PhysRevB.57.7488 PG 3 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300023 ER PT J AU Kim, JT Park, YK Park, JC Lim, HR Shim, SY Kim, DH Kang, WN Park, JH Hahn, TS Choi, SS Lee, WC Hettinger, JD Gray, KE AF Kim, JT Park, YK Park, JC Lim, HR Shim, SY Kim, DH Kang, WN Park, JH Hahn, TS Choi, SS Lee, WC Hettinger, JD Gray, KE TI Pinning effect on fluctuation conductivity in a superconducting untwinned YBa2Cu3O7-delta single crystal with columnar defects SO PHYSICAL REVIEW B LA English DT Article ID CRITICAL-BEHAVIOR; STATE; HEAT AB The effect of columnar defects on the critical dynamics of a superconducting untwinned YBa2Cu3O7-delta (YBCO) single crystal has been investigated. The columnar defects are produced by Sn ion irradiation of which dose corresponds to a matching field of 1 T. The in-plane longitudinal resistivity of the irradiated YBCO crystal has been measured as a function of magnetic field H and temperature T. The extracted fluctuation conductivities are enhanced by the strong pinnings and do not exhibit the same three-dimensional (3D) XY scaling behavior as for the unirradiated YBCO single crystal; particularly at the magnetic field values near the matching field of 1 T, the fluctuation conductivities show a clear deviation from the critical dynamics. At higher magnetic fields, however, the signature of the 3D-XY scaling appears. C1 Korea Res Inst Stand & Sci, Superconduct Grp, Taejon, South Korea. Yeungnam Univ, Dept Phys, Kyongsan 712749, South Korea. Korea Inst Sci & Technol, Superconduct Res Grp, Seoul 130650, South Korea. Sookmyung Womans Univ, Seoul 140742, South Korea. Argonne Natl Lab, Argonne, IL 60439 USA. RP Kim, JT (reprint author), Korea Res Inst Stand & Sci, Superconduct Grp, POB 102, Taejon, South Korea. NR 16 TC 7 Z9 7 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7499 EP 7502 DI 10.1103/PhysRevB.57.7499 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300026 ER PT J AU Ankudinov, AL Conradson, SD de Leon, JM Rehr, JJ AF Ankudinov, AL Conradson, SD de Leon, JM Rehr, JJ TI Relativistic XANES calculations of Pu hydrates SO PHYSICAL REVIEW B LA English DT Article ID X-RAY-ABSORPTION; NEAR-EDGE STRUCTURE; MULTIPLE-SCATTERING CALCULATIONS; FINE-STRUCTURE; CIRCULAR-DICHROISM; TRANSITION-METALS; URANYL-ION; K-EDGE; SPECTRA; EXAFS AB A theoretical analysis of x-ray absorption near edge structure (XANES) at L-3 and L-1 edges for Pu hydrates with a formal oxidation state of Pu ranging from +3 to +6, using the ab initio multiple scattering code FEFF7, is presented. For each hydrate our calculations reproduce well the white line intensity and relative peak positions, which are the features commonly used for formal valence identification. In order to achieve such a degree of coincidence between theory and experiment, it was necessary to use a relativistic Dirac-Fock treatment of atomic densities and mixed Dirac-Fock-local-density-approximation exchange-correlation potentials, not considered in previous actinide studies. We find that most of the white line intensity at L-3 edges originates from scattering of the photoelectron, i.e., x-ray absorption fine structure. We also show that the white line shoulder peak, present in the case of plutonyl compounds (Pu5+ and Pu6+), is due largely to constructive interference of scattering paths containing axial oxygens. Limitations of the FEFF7 code and ways to improve the quantitative agreement between XANES calculations and experimental spectra are also discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. IPN, Ctr Invest & Estudios Avanzados, Dept Appl Phys, Merida 97310, Yucatan, Mexico. Univ Washington, Dept Phys, Seattle, WA 98195 USA. RP Ankudinov, AL (reprint author), Univ Calif Los Alamos Natl Lab, MST-11, Los Alamos, NM 87545 USA. RI Mustre de Leon, Jose/B-5630-2009 OI Mustre de Leon, Jose/0000-0002-0513-2323 NR 54 TC 73 Z9 73 U1 1 U2 17 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7518 EP 7525 DI 10.1103/PhysRevB.57.7518 PG 8 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300031 ER PT J AU Nordlund, K Ghaly, M Averback, RS Caturla, M de la Rubia, TD Tarus, J AF Nordlund, K Ghaly, M Averback, RS Caturla, M de la Rubia, TD Tarus, J TI Defect production in collision cascades in elemental semiconductors and fcc metals SO PHYSICAL REVIEW B LA English DT Article ID MOLECULAR-DYNAMICS SIMULATION; ENERGETIC DISPLACEMENT CASCADES; EMBEDDED-ATOM METHOD; INTERATOMIC POTENTIALS; COMPUTER-SIMULATION; TRANSITION-METALS; ALPHA-IRON; X-RAY; SILICON; SI AB A comparative molecular dynamics simulation study of collision cascades in two elemental semiconductors and five fee metals is performed to elucidate how different material characteristics affect primary defect production during ion irradiation. By using simulations of full 400 eV-10 keV collision cascades and contrasting the results on different materials with each other, we probe the effect of the mass, melting temperature, material strength, and crystal structure on the modification of the material due to the cascade. The results show that the crystal structure has a strong effect on many aspects of damage production, while other material characteristics are of lesser overall importance. In all materials studied, isolated point defects produced by the cascade are predominantly interstitials. In semiconductors, amorphous clusters are produced in the cascade core, whereas in metals most of the crystal regenerates, leaving only small vacancy-rich clusters. Large interstitial clusters found in a few events in the heavy metals were observed to form by the isolation of a high-density liquid zone during the recrystallization phase of a cascade. C1 Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. Univ Helsinki, Accelerator Lab, FIN-00014 Helsinki, Finland. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Univ Illinois, Mat Res Lab, Urbana, IL 61801 USA. RI Caturla, Maria /D-6241-2012; Nordlund, Kai/L-8275-2014 OI Caturla, Maria /0000-0002-4809-6553; Nordlund, Kai/0000-0001-6244-1942 NR 71 TC 424 Z9 427 U1 8 U2 69 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7556 EP 7570 DI 10.1103/PhysRevB.57.7556 PG 15 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300036 ER PT J AU Gierer, M Van Hove, MA Goldman, AI Shen, Z Chang, SL Pinhero, PJ Jenks, CJ Anderegg, JW Zhang, CM Thiel, PA AF Gierer, M Van Hove, MA Goldman, AI Shen, Z Chang, SL Pinhero, PJ Jenks, CJ Anderegg, JW Zhang, CM Thiel, PA TI Fivefold surface of quasicrystalline AlPdMn: Structure determination using low-energy-electron diffraction SO PHYSICAL REVIEW B LA English DT Article ID SINGLE QUASI-CRYSTALS; MN ICOSAHEDRAL PHASE; LEED; AL68PD23MN9; ALLOYS; ADSORPTION; SPECTRA; METALS; GRAIN; SIZE AB The atomic structure of the fivefold symmetric quasicrystal surface of icosahedral AlPdMn has been investigated by means of a dynamical low-energy-electron diffraction (LEED) analysis. Approximations were developed to make the structure of an aperiodic, quasicrystalline surface region accessible to LEED theory. A mix of several closely similar, relaxed, bulklike lattice terminations is favored, all of which have a dense Al-rich layer on top followed by a layer with a composition of about 50% Al and 50% Pd. The interlayer spacing between these two topmost layers is contracted from the bulk value by 0.1 Angstrom, to a final value of 0.38 Angstrom, and the lateral density of the two topmost layers taken together is similar to that of an Al(111) surface. The LEED structural result is qualitatively consistent with data from ion scattering spectroscopy, which supports an Al-rich termination. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Gierer, M (reprint author), Univ Munich, Inst Kristallog & Mineral, Theresienstr 41, D-80333 Munchen, Germany. RI Van Hove, Michel/A-9862-2008 OI Van Hove, Michel/0000-0002-8898-6921 NR 55 TC 123 Z9 123 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7628 EP 7641 DI 10.1103/PhysRevB.57.7628 PG 14 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300044 ER PT J AU Faulkner, JS Moghadam, NY Wang, Y Stocks, GM AF Faulkner, JS Moghadam, NY Wang, Y Stocks, GM TI Evaluation of isomorphous models of alloys SO PHYSICAL REVIEW B LA English DT Article ID COHERENT-POTENTIAL APPROXIMATION; ELECTRONIC-STRUCTURE CALCULATIONS; RANDOM SUBSTITUTIONAL ALLOYS; SITE DIAGONAL DISORDER; 3-DIMENSIONAL ALLOY; TOTAL-ENERGY; SCATTERING; SYSTEMS; ORDER; TRANSITION AB Order-N methods for calculating the electronic structure of clusters containing hundreds of atoms using realistic self-consistent density-functional theory local-density approximation potentials make it possible to test alloy theories more definitively. Tests are carried out on isomorphous models of alloys in which the atoms of each species are treated as identical. In contrast, the order-N calculations lead to a polymorphous model in which all of the atoms are unique. Isomorphous models are seen to reproduce average densities of states and cohesive energies surprisingly well, in spite of their deficiencies in other areas. C1 Florida Atlantic Univ, Alloy Res Ctr, Boca Raton, FL 33431 USA. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. Pittsburgh Supercomp Ctr, Pittsburgh, PA 15213 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37830 USA. RP Faulkner, JS (reprint author), Florida Atlantic Univ, Alloy Res Ctr, Boca Raton, FL 33431 USA. RI Stocks, George Malcollm/Q-1251-2016 OI Stocks, George Malcollm/0000-0002-9013-260X NR 55 TC 16 Z9 16 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7653 EP 7660 DI 10.1103/PhysRevB.57.7653 PG 8 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300046 ER PT J AU Lei, G Anderson, JE Buchwald, MI Edwards, BC Epstein, RI AF Lei, G Anderson, JE Buchwald, MI Edwards, BC Epstein, RI TI Determination of spectral linewidths by Voigt profiles in Yb3+-doped fluorozirconate glasses SO PHYSICAL REVIEW B LA English DT Article ID OPTICAL HOMOGENEOUS LINEWIDTHS; INORGANIC GLASSES; FRACTON CONTRIBUTION; FLUORIDE GLASSES; IONS; SPECTROSCOPY; TRANSITIONS; DEPENDENCE; WIDTHS; STATE AB Homogeneous and inhomogeneous spectral linewidths of the (F-2(5/2))(1) - (F-2(7/2))(1) transition in Yb3+-doped fluorozirconate glasses are determined by fitting Voigt profiles to the inhomogeneously broadened emission and absorption spectra between 10 and 300 K. The homogeneous linewidth varied as (12 +/- 2) chi T(1.9 +/- 0.1) MHz for emission and (10 +/- 1) chi T1.9 +/- 0.1 for absorption over the entire temperature range, similar to that of other rare-earth-doped systems previously studied by fluorescence line narrowing and photon echoes. The inhomogeneous linewidths were nearly independent of temperature, but different by similar to 30% between emission and absorption. The structural and dynamic properties in this disordered system an discussed. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Lei, G (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 36 TC 38 Z9 38 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7673 EP 7678 DI 10.1103/PhysRevB.57.7673 PG 6 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300049 ER PT J AU Woods, LM Mahan, GD AF Woods, LM Mahan, GD TI Nonlinear electron-phonon heat exchange SO PHYSICAL REVIEW B LA English DT Article ID ACOUSTIC POLARON; METALS AB A calculation of the energy exchange between phonons and electrons is done for a metal at very low temperatures. We consider the energy exchange due to two-phonon processes. Second-order processes are expected to be important at temperatures less than 1 K. We include two different second-order processes: (i) the Compton-Like scattering of phonons, and (ii) the electron-dual-phonon scattering from the second-order electron-phonon interaction. It is found that the Compton-like process contains a singular energy denominator. The singularity is removed by introducing quasiparticle damping. For pure metals we find that the energy exchange depends upon the lifetime of the electrons and it is proportional to the temperature of the lattice as T-L(8). The same calculation is performed for the electron-dual-phonon scattering and it is found that the temperature dependence is T-L(9). The results can be applied to quantum dot refrigerators. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Woods, LM (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 13 TC 1 Z9 1 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7679 EP 7685 DI 10.1103/PhysRevB.57.7679 PG 7 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300050 ER PT J AU Mal'shukov, AG Mahan, GD AF Mal'shukov, AG Mahan, GD TI Nonlinear forward scattering of light in opaque media SO PHYSICAL REVIEW B LA English DT Article ID LOCALIZATION; FLUCTUATIONS AB Because of disorder, the intensity of light diffusively propagating in a weakly absorbing opaque medium fluctuates randomly from one point to the another. If the light intensity is large enough the third-order nonlinearity, in combination with intensity fluctuations of the pump light, gives rise to an angular scattering of the probe wave. We have shown that because of long-range correlations of the intensity fluctuations the angular distribution of the probe wave incident on a thin slab and scattered in the forward direction has a narrow peak at small scattering angles. The shape of this peak depends on the boundary conditions on the surface of the slab. If the surface of the slab strongly reflects the pump photons the peak becomes narrower and much more intense than in the case of a weak reflection. C1 Russian Acad Sci, Inst Spect, Moscow 142092, Russia. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Mal'shukov, AG (reprint author), Russian Acad Sci, Inst Spect, Moscow 142092, Russia. NR 12 TC 1 Z9 1 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7701 EP 7704 DI 10.1103/PhysRevB.57.7701 PG 4 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300053 ER PT J AU Sarrao, JL Modler, R Movshovich, R Lacerda, AH Hristova, D Cornelius, AL Hundley, MF Thompson, JD Benton, CL Immer, CD Torelli, ME Martins, GB Fisk, Z Oseroff, SB AF Sarrao, JL Modler, R Movshovich, R Lacerda, AH Hristova, D Cornelius, AL Hundley, MF Thompson, JD Benton, CL Immer, CD Torelli, ME Martins, GB Fisk, Z Oseroff, SB TI Ferromagnetism and crystal fields in YbInNi4 SO PHYSICAL REVIEW B LA English DT Article ID VALENCE PHASE-TRANSITION; NEUTRON-SCATTERING; MAGNETIC-FIELDS; KONDO-LATTICE; PRESSURE; YBINCU4; YBNISN; HEAT; YBXIN1-XCU2; RESISTIVITY AB We present transport and thermodynamic measurements as a function of temperature (0.1-300 K), pressure (1 bar-16 kbars), and magnetic field (0-600 kOe) on YbInNi4. Ferromagnetism arises near 3 K out of a state with enhanced electronic specific-heat coefficient. Resistivity, specific-heat, and magnetization measurements imply that the ground state of YbInNi4 is a crystal-field doublet, whereas earlier neutron-scattering results suggest a ground-state quartet. We also compare YbInNi4 to YbInCu4 and intermediate alloys. C1 Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. San Diego State Univ, Dept Phys, San Diego, CA 92182 USA. RP Sarrao, JL (reprint author), Florida State Univ, Natl High Magnet Field Lab, Tallahassee, FL 32306 USA. RI Cornelius, Andrew/A-9837-2008; Martins, George/C-9756-2012 OI Martins, George/0000-0001-7846-708X NR 46 TC 21 Z9 21 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7785 EP 7790 DI 10.1103/PhysRevB.57.7785 PG 6 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300060 ER PT J AU Hammar, PR Reich, DH Broholm, C AF Hammar, PR Reich, DH Broholm, C TI Spin gap in a quasi-one-dimensional S=1/2 antiferromagnet: Cu-2(1,4-diazacloheptane)(2)Cl-4 SO PHYSICAL REVIEW B LA English DT Article ID EXCITATION SPECTRUM; LADDER; CHAINS; SYSTEM; SUSCEPTIBILITY; COMPOUND AB Cu-2(1,4-diazacycloheptane)(2)Cl-4 contains double chains of spin-1/2 Cu2+ ions. We report ac susceptibility, specific heat, and inelastic neutron-scattering measurements on this material. The magnetic susceptibility chi(T) shows a rounded maximum at T = 8 K indicative of a low-dimensional antiferromagnet with no zero-field magnetic phase transition. We compare the chi(T) data with exact diagonalization results for various one-dimensional spin Hamiltonians and find excellent agreement for a spin ladder with intrarung coupling J(1) = 1.143(3) meV and two mutually frustrating interrung interactions J(2) = 0.21(3) meV and J(3) = 0.09(5) meV. The specific heat in zero field is exponentially activated with an activation energy Delta = 0.87(1) meV. A spin gap is also found through inelastic neutron scattering on powder samples that identify a band of magnetic excitations for 0.8<(h) over bar omega<1.5 meV. Using sum rules we derive an expression for the dynamic spin-correlation function associated with noninteracting propagating triplets in a spin ladder. The Van Hove singularities of such a model are not observed in our scattering data, indicating that magnetic excitations in Cu-2(1,4-diazacycloheptane)(2)Cl-4 are more complicated. For magnetic fields above H(cl)similar or equal to 7.2 T specific-heat data versus temperature show anomalies indicating a phase transition to an ordered state below T = 1 K. C1 Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. Argonne Natl Lab, IPNS, Argonne, IL 60439 USA. RP Hammar, PR (reprint author), Johns Hopkins Univ, Dept Phys & Astron, Baltimore, MD 21218 USA. RI Broholm, Collin/E-8228-2011 OI Broholm, Collin/0000-0002-1569-9892 NR 33 TC 79 Z9 79 U1 0 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7846 EP 7853 DI 10.1103/PhysRevB.57.7846 PG 8 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300069 ER PT J AU Bullock, M Zarestky, J Stassis, C Goldman, A Canfield, PC Honda, Z Shirane, G Shapiro, SM AF Bullock, M Zarestky, J Stassis, C Goldman, A Canfield, PC Honda, Z Shirane, G Shapiro, SM TI Low-energy phonon excitations in superconducting RNiB2C (R = Lu, Y) SO PHYSICAL REVIEW B LA English DT Article ID INELASTIC-NEUTRON-SCATTERING; NICKEL BORIDE CARBIDES; MAGNETIC-STRUCTURE; LUNI2B2C; LNNI2B2C; ERNI2B2C; ORDER; NB3SN AB Inelastic neutron-scattering techniques have been used to study the low-energy phonon excitations in superconducting RNi2B2C (R = Lu, Y) to further characterize the anomalous features observed by Kawano et al. [Phys. Rev. Lett. 77, 4628 (1996)] for R = Y and Stassis et al. [Phys. Rev. B 55, R8678 (1997)] for R = Lu, when these systems enter the superconducting ground state. We find that above T, the frequencies of the Delta(4)[xi 00] lowest-lying acoustic and optic phonon modes decrease with decreasing temperature, for xi close to the nesting vector xi(m). In addition there is a shift of intensity from the upper to the lower mode, an effect characteristic of mode coupling. The observed intensity transfer between these modes above T-c can be described satisfactorily in both compounds by a coupled-mode model. Below T-c the observed spectrum changes dramatically: it consists of a sharp peak at approximately 4 meV with a broad weak shoulder at higher energies. The experimental results unambiguously show that this dramatic change is due to the onset of superconductivity in these compounds. In this temperature region, the results are in qualitative agreement with recent theoretical calculations. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RIKEN, Inst Phys & Chem Res, Wako, Saitama 35101, Japan. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RI Canfield, Paul/H-2698-2014 NR 35 TC 37 Z9 37 U1 1 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 7916 EP 7921 DI 10.1103/PhysRevB.57.7916 PG 6 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300078 ER PT J AU Koshelev, AE Vinokur, VM AF Koshelev, AE Vinokur, VM TI Pinning-induced transition to disordered vortex phase in layered superconductors SO PHYSICAL REVIEW B LA English DT Article ID HIGH-TEMPERATURE SUPERCONDUCTORS; DIFFERENT OXYGEN STOICHIOMETRY; HIGH-MAGNETIC-FIELD; FLUX-LINE-LATTICE; II SUPERCONDUCTORS; SINGLE-CRYSTALS; ANOMALOUS MAGNETIZATION; BI2SR2CACU2O8 CRYSTALS; DIMENSIONAL CROSSOVER; THERMAL FLUCTUATIONS AB Destruction of the vortex lattice by random point pinning is considered as a mechanism of the "second peak" transition observed experimentally in weakly coupled layered high-temperature superconductors. The transition field separating the topologically ordered quasilattice from the amorphous vortex configuration is strongly influenced by the layered structure and by the nonlocal nature of the vortex tilt energy due to the magnetic interlayer coupling. We found three different regimes of transition depending on the relative strength of the Josephson and magnetic couplings. The regimes can be distinguished by the dependence of the transition field on the superconductor parameters and pinning strength. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Koshelev, AE (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Koshelev, Alexei/K-3971-2013 OI Koshelev, Alexei/0000-0002-1167-5906 NR 57 TC 89 Z9 89 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 13 BP 8026 EP 8033 DI 10.1103/PhysRevB.57.8026 PG 8 WC Physics, Condensed Matter SC Physics GA ZH082 UT WOS:000073070300090 ER PT J AU Cuello, GJ Bermejo, FJ Fayos, R Fernandez-Perea, R Criado, A Trouw, F Tam, C Schober, H Enciso, E Almarza, NG AF Cuello, GJ Bermejo, FJ Fayos, R Fernandez-Perea, R Criado, A Trouw, F Tam, C Schober, H Enciso, E Almarza, NG TI Anharmonic dynamics in crystalline, glassy, and supercooled-liquid glycerol: A case study on the onset of relaxational behavior SO PHYSICAL REVIEW B LA English DT Article ID COHERENT NEUTRON-SCATTERING; VISCOUS GLYCEROL; MICROSCOPIC DYNAMICS; TRANSITION; MOTION; FORMERS AB The temperature dependence of the spectral distributions of the glass, crystalline, and supercooled-liquid phases of glycerol is investigated by means of neutron inelastic scattering. The importance of anharmonic effects is quantified by the temperature dependence of reduced spectral frequency moments. The onset of relaxational (i.e., stochastic, zero-frequency) motions in the supercooled liquid state is monitored by neutron quasielastic scattering. A substantial deviation of the observed linewidths from the hydrodynamic prescription is observed and is interpreted at a microscopic level, by comparison with the crystalline phase. C1 CSIC, E-28006 Madrid, Spain. Argonne Natl Lab, Argonne, IL 60439 USA. Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. Univ Complutense, Dept Quim Fis 1, E-28040 Madrid, Spain. RP CSIC, Serrano 123, E-28006 Madrid, Spain. RI Almarza, N/A-5058-2009; Cuello, Gabriel/C-5831-2009; Fernandez-Perea, Ricardo/E-9118-2016 OI Almarza, N/0000-0002-3771-6649; Cuello, Gabriel/0000-0003-3844-0602; Fernandez-Perea, Ricardo/0000-0002-4011-2344 NR 47 TC 13 Z9 13 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2469-9950 EI 2469-9969 J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP 8254 EP 8263 DI 10.1103/PhysRevB.57.8254 PG 10 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400035 ER PT J AU Tkachuk, A Rogacki, K Brown, DE Dabrowski, B Fedro, AJ Kimball, CW Pyles, B Xiong, X Rosenmann, D Dunlap, BD AF Tkachuk, A Rogacki, K Brown, DE Dabrowski, B Fedro, AJ Kimball, CW Pyles, B Xiong, X Rosenmann, D Dunlap, BD TI Dynamics of phase stability and magnetic order in magnetoresistive (La0.83Sr0.17Mn0.98Fe0.02O3)-Fe-57 SO PHYSICAL REVIEW B LA English DT Article ID LA1-XSRXMNO3; TRANSITION; LA(1-X)A(X)MNO(3); LA1-XCAXMNO3; FIELD AB Two samples with the same nominal composition (La0.83Sr0.17Mn0.98Fe0.02O3)-Fe-57 were prepared in air and argon. Thermograviametric, structural, resistive, and magnetic measurements show that the air-made sample has slightly higher Mn4+/Mn3+ ratio; i.e., it is slightly more highly doped by similar to -0.15% cation vacancies. Substitution of Fe for Mn depresses the ferromagnetic transition temperature T-c but has very small effect on the rhombohedral/orthorhombic structural phase boundary. Dramatic differences are found in transport properties for small differences in Mn4+ concentration near a structural and magnetic phase boundary. The dynamics of charge hopping and exchange via the effect of relaxation of the magnetic hyperfine field distribution and its average value are monitored by temperature-dependent Mossbauer effect measurements. Ferromagnetic clustering is observed above T-c at Fe-57 sites. The compound undergoes complex temperature dependent magnetic and phase behaviors that are monitored locally by the Fe-57 Mossbauer effect. The iron probe has a stable 3+ valance configuration whose hyperfine interaction reflects the structural phase changes, the Jahn-Teller distortion and the time-dependent Mn3+-Mn4+ charge fluctuations. It is shown that regions of magnetic order exist over similar to 100 K range beginning well above T-c. Moreover, the low-temperature structural phase. reported to be orthorhombic at this composition, shows dynamic magnetic fluctuation behavior that motionally narrows at low temperature. Any changes in hyperfine interaction due to the structural transition are masked by the fluctuating magnetic behavior, but clearly the two structures coexist in the temperature region near T-c. C1 Polish Acad Sci, Inst Low Temp & Struct Res, PL-50950 Wroclaw, Poland. No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Tkachuk, A (reprint author), No Illinois Univ, Dept Phys, De Kalb, IL 60115 USA. NR 32 TC 57 Z9 60 U1 0 U2 7 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP 8509 EP 8517 DI 10.1103/PhysRevB.57.8509 PG 9 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400060 ER PT J AU Zhu, YM Li, Q Tsay, YN Suenaga, M Gu, GD Koshizuka, N AF Zhu, YM Li, Q Tsay, YN Suenaga, M Gu, GD Koshizuka, N TI Structural origin of misorientation-independent superconducting behavior at [001] twist boundaries in Bi2Sr2CaCu2O8+delta SO PHYSICAL REVIEW B LA English DT Article ID YBA2CU3O7-DELTA GRAIN-BOUNDARIES; SILVER-SHEATHED TAPES; ELASTIC-CONSTANTS; CRITICAL CURRENTS; BICRYSTALS; TRANSPORT; MODEL; TEM AB A systematic investigation of the structure and properties of [001] twist boundaries was made in Bi2Sr2CaCu2O8+delta bicrystals. Contrary to conventional wisdom, all these boundaries, regardless of their misorientation angle, carried almost the same critical current as their constituent single crystals at magnetic fields up to 9 t. The origin of this misorientation-independent superconducting behavior at twist boundaries was sought by detailed structural characterization using high-resolution and nanoprobe transmission-electron microscopy. The robust electromagnetic properties of these grain boundaries were mainly attributed to the high anisotropy of the crystals, and to the softness of the double BiO layers at the boundaries which allow the CuO2 layers adjacent to the boundary plane to remain undisturbed. The structural characteristics of these boundaries are identical to those found in Bi2Sr2CaCu2O8+delta and Bi2Sr2Ca2Cu3O10+delta tapes, suggesting that the large-angle [001] twist boundaries are not a current-limiting obstacle in this important conductor. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Univ New S Wales, Sch Phys, Kensington, NSW 2033, Australia. ISTEC, Superconduct Res Lab, Koto Ku, Tokyo 135, Japan. RP Zhu, YM (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 46 TC 49 Z9 49 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP 8601 EP 8608 DI 10.1103/PhysRevB.57.8601 PG 8 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400070 ER PT J AU Abrikosov, AA AF Abrikosov, AA TI Neutron peak in the extended-saddle-point model of high-temperature superconductors SO PHYSICAL REVIEW B LA English DT Article ID ORDER-PARAMETER; SCATTERING; YBA2CU3O6+X AB An explanation is proposed of the maximum at 41 meV in the inelastic spin-flip neutron scattering from YBa2Cu3O7-delta, based on the extended-saddle-point model developed by the author in his previous works. It is shown that for appearance of the maximum in the imaginary part of the spin susceptibility a close proximity of the Fermi energy to the extended saddle point is necessary. The energy of the maximum is then close to 2 Delta(max) in agreement with experiment. Theoretical and experimental evidence concerning the energy of the extended saddle point (flat region) is discussed. Different limiting cases are calculated. A proof is given within the present model that interaction in the final state is small, and hence, no collective modes are formed. A general discussion of the experimental situation is presented. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Abrikosov, AA (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 24 TC 29 Z9 29 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP 8656 EP 8661 DI 10.1103/PhysRevB.57.8656 PG 6 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400075 ER PT J AU Arulraj, A Biswas, A Raychaudhuri, AK Rao, CNR Woodward, PM Vogt, T Cox, DE Cheetham, AK AF Arulraj, A Biswas, A Raychaudhuri, AK Rao, CNR Woodward, PM Vogt, T Cox, DE Cheetham, AK TI Reentrant transition from an incipient charge-ordered state to a ferromagnetic metallic state in a rare-earth manganate SO PHYSICAL REVIEW B LA English DT Article ID GIANT MAGNETORESISTANCE; MAGNETIC-FIELD; DOPED LAMNO3; PEROVSKITES; OXIDE; LA1-XCAXMNO3; SYSTEMS AB A reentrant transition from an incipient charge-ordered (CO) state to a charge-delocalized ferromagnetic (CDFM) state has been established in the manganate Nd0.25La0.25Ca0.5MnO3, in which the average A-site ionic radius is 1.19 Angstrom. The reentrant CDFM phase is associated with a first-order phase transition that reduces the orthorhombic distortion of the lattice, in contrast to the CO transition in other manganates where the orthorhombically distorted CO state is stabilized at low temperatures. At the CO-CDFM transition, there is a collapse of the charge-ordering gap as measured by vacuum tunneling spectroscopy. C1 Indian Inst Sci, Solid State & Struct Chem Unit, Bangalore 560012, Karnataka, India. Indian Inst Sci, Dept Phys, Bangalore 560012, Karnataka, India. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Calif Santa Barbara, Mat Res Lab, Santa Barbara, CA 93106 USA. RP Arulraj, A (reprint author), Indian Inst Sci, Solid State & Struct Chem Unit, Bangalore 560012, Karnataka, India. EM cnrrao@sscu.iisc.ernet.in RI Rao, C.N.R./B-1569-2009; Raychaudhuri, Arup/D-3826-2009; Vogt, Thomas /A-1562-2011; Ahirwal, Ashish /F-2532-2013 OI Rao, C.N.R./0000-0003-4088-0615; Vogt, Thomas /0000-0002-4731-2787; Ahirwal, Ashish /0000-0002-9127-6541 NR 29 TC 22 Z9 22 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP R8115 EP R8118 DI 10.1103/PhysRevB.57.R8115 PG 4 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400015 ER PT J AU Morozov, N Maley, MP Bulaevskii, LN Sarrao, J AF Morozov, N Maley, MP Bulaevskii, LN Sarrao, J TI Reentrant c-axis magnetoresistance in Bi2Sr2CaCu2O8+delta with columnar defects: Evidence for recoupling of the vortex liquid SO PHYSICAL REVIEW B LA English DT Article ID LATTICE PHASE-TRANSITION; FLUX-LINE-LATTICE; REVERSIBLE MAGNETIZATION; SINGLE-CRYSTALS; SUPERCONDUCTORS; YBA2CU3O7-DELTA; RESISTIVITY; TRANSPORT; FIELDS AB We present c-axis magnetoresistance and I-V measurements in longitudinal magnetic field in single crystals of Bi2Sr2CaCu2O8+delta irradiated with heavy ions that display distinct anomalies near fractional filling of the columnar defects created by the irradiation. The anomalous behavior extends over a limited range of temperature and, in many crystals, is manifested by a minimum in rho(c)(H). The region of temperature-field where these anomalies appear coincides with that where two Josephson-plasma resonance lines have been recently observed. Our measurements directly show that a reduced pancake and phase slip mobility is associated with columnar defect filling in the vortex liquid state. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Morozov, N (reprint author), Univ Calif Los Alamos Natl Lab, MS-K763, Los Alamos, NM 87545 USA. NR 23 TC 16 Z9 16 U1 1 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP R8146 EP R8149 DI 10.1103/PhysRevB.57.R8146 PG 4 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400023 ER PT J AU Nikitenko, VI Gornakov, VS Dedukh, LM Kabanov, YP Khapikov, AF Shapiro, AJ Shull, RD Chaiken, A Michel, RP AF Nikitenko, VI Gornakov, VS Dedukh, LM Kabanov, YP Khapikov, AF Shapiro, AJ Shull, RD Chaiken, A Michel, RP TI Asymmetry of domain nucleation and enhanced coercivity in exchange-biased epitaxial NiO/NiFe bilayers SO PHYSICAL REVIEW B LA English DT Article ID GIANT MAGNETORESISTANCE; ANISOTROPY; FILMS; INTERFACES; LAYERS; MODEL; NIO AB Magnetization reversal processes in epitaxial NiO/NiFe bilayers were studied using the magneto-optic indicator film technique. The influence of dislocations on these processes was determined. Remagnetization parallel to the unidirectional anisotropy axis proceeds by domain nucleation and growth, with nucleation center activity being asymmetric with respect to the applied field sign. Magnetization reversal in the hard axis direction occurs by incoherent rotation. The enhanced coercivity and asymmetric nucleation can be explained by taking into account domain wall behavior in the antiferromagnetic layer. C1 Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Moscow District, Russia. NIST, Div Met, Gaithersburg, MD 20899 USA. Univ Calif Lawrence Livermore Natl Lab, Div Mat Sci & Technol, Livermore, CA 94551 USA. RP Nikitenko, VI (reprint author), Russian Acad Sci, Inst Solid State Phys, Chernogolovka 142432, Moscow District, Russia. RI Shull, Robert/F-5971-2013 NR 21 TC 80 Z9 80 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD APR 1 PY 1998 VL 57 IS 14 BP R8111 EP R8114 DI 10.1103/PhysRevB.57.R8111 PG 4 WC Physics, Condensed Matter SC Physics GA ZH083 UT WOS:000073070400014 ER PT J AU Fotiades, N Cizewski, JA McNabb, DP Ding, KY Archer, DE Becker, JA Bernstein, LA Hauschild, K Younes, W Clark, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW AF Fotiades, N Cizewski, JA McNabb, DP Ding, KY Archer, DE Becker, JA Bernstein, LA Hauschild, K Younes, W Clark, RM Fallon, P Lee, IY Macchiavelli, AO MacLeod, RW TI Weak coupling and dipole bands in Pb-191 SO PHYSICAL REVIEW C LA English DT Article ID SHEARS BANDS; COLLECTIVE OBLATE; 1ST OBSERVATION; ROTATIONAL BANDS; BISMUTH NUCLEI; SHELL-MODEL; STATES; PB-200; REGION; HG-193 AB Excited states in the nucleus Pb-191 have been investigated by in-beam gamma-ray spectroscopic techniques using the Gammasphere array. The reaction Yb-173(Mg-24,6n) at a beam energy of 134.5 MeV was used to populate states of Pb-191. The level scheme of Pb-191 has been extended up to 5.1 MeV excitation energy and spin 45/2. The lower part (below approximate to 2.3 MeV) presents the general features common in all odd-mass Pb isotopes, i.e., spherical states built on the 13/2(+) isomer, with bandlike structures that follow weak-coupling expectations. In the upper part of the level scheme two dipole bands are observed with bandhead energies of similar to 2.512 and 2.291 MeV. A comparison of dipole band 1 with the strongest negative-parity dipole bands in the heavier odd-mass Pb isotopes reveals striking similarities. The spherical states are interpreted as the coupling of the i(13/2) neutron hole to the yrast states in the even-mass Pb-192 Core. The dipole bands are interpreted as M1 cascades which arise from the coupling of two protons in high-j orbitals above the Z=82 gap to neutron holes in the i(13/2)orbital. [S0556-2813(98)02504-7]. C1 Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. RP Fotiades, N (reprint author), Rutgers State Univ, Dept Phys & Astron, New Brunswick, NJ 08903 USA. RI Hauschild, Karl/A-6726-2009 NR 42 TC 19 Z9 19 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 1624 EP 1633 DI 10.1103/PhysRevC.57.1624 PG 10 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700012 ER PT J AU Turler, A Dressler, R Eichler, B Gaggeler, HW Jost, DT Schadel, M Bruchle, W Gregorich, KE Trautmann, N Taut, S AF Turler, A Dressler, R Eichler, B Gaggeler, HW Jost, DT Schadel, M Bruchle, W Gregorich, KE Trautmann, N Taut, S TI Decay properties of (265)Sg(Z=106) and (266)Sg(Z=106) SO PHYSICAL REVIEW C LA English DT Article ID ELEMENT 106; DISCOVERY; NUCLEI AB The presently known most neutron-rich isotopes of element 106 (seaborgium, Sg), (265)Sg and (266)Sg, were produced in the fusion reaction Ne-22+ Cm-248 at beam energies of 121 and 123 MeV. Using the On-Line Gas chemistry Apparatus OLGA, a continuous separation of Sg was achieved within a few seconds. Final products were assayed by alpha-particle and spontaneous fission (SF) spectrometry. (265)Sg and (266)Sg were identified by observing time correlated alpha-alpha-(alpha) and alpha-SF decay chains. A total of 13 correlated decay chains of (265)Sg (With an estimated number of 2.8 random correlations) and 3 decay chains of (266)Sg (0.6 random correlations) were identified. Deduced decay properties were T-1/2=7.4(-2.7)(+3.3) s (68% c.i.) and E-alpha=8.69 MeV (8%), 8.76 MeV (23%), 8.84 MeV (46%), and 8.94 MeV (23%) for (265)Sg; and T-1/2=21(-12)(+20) s (68% c.i.) and E-alpha=8.52 MeV (33%) and 8.77 MeV (66%) for (266)Sg. The resolution of the detectors was between 50-100 keV (full width at half maximum). Upper limits for SF of less than or equal to 35% and less than or equal to 82% were established for (265)Sg and (266)Sg, respectively. The upper limits for SF are given with a 16% error probability. Using the lower error limits of the half-lives of (265)Sg and (266)Sg, the resulting lower limits for the partial SF half-lives are T-1/2(SF)((265)Sg)greater than or equal to 13 s and T-1/2(SF)((266)Sg)greater than or equal to 11 s. Correspondingly, the partial alpha-decay half-lives are between T-1/2(alpha)((265)Sg)=4.7-16.5 s (68% c.i.) and T-1/2(alpha)((266)Sg)=9-228 s (68% c.i.), using the upper and lower error limits of the half-lives of (265)Sg and (266)Sg. The lower limit on the partial SF half-life of (266)Sg is in good agreement with theoretical predictions. Production cross sections of about 240 pb and 25 pb for the alpha-decay branch in (265)Sg and (266)Sg were estimated, respectively. [S0556-2813(98)05604-0]. C1 Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Univ Bern, Dept Chem & Biochem, CH-3012 Bern, Switzerland. Gesell Schwerionenforsch mbH, D-64291 Darmstadt, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Mainz, Inst Kernchem, D-55099 Mainz, Germany. Rossendorf Inc, Forschungszentrum Rossendorf EV, Inst Radiochem, D-01314 Dresden, Germany. RP Turler, A (reprint author), Paul Scherrer Inst, CH-5232 Villigen, Switzerland. RI Turler, Andreas/D-3913-2014 OI Turler, Andreas/0000-0002-4274-1056 NR 22 TC 59 Z9 60 U1 2 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 1648 EP 1655 DI 10.1103/PhysRevC.57.1648 PG 8 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700014 ER PT J AU Heenen, PH Dobaczewski, J Nazarewicz, W Bonche, P Khoo, TL AF Heenen, PH Dobaczewski, J Nazarewicz, W Bonche, P Khoo, TL TI Shell effects in superdeformed minima SO PHYSICAL REVIEW C LA English DT Article ID ATOMIC MASS EVALUATION; MEAN-FIELD; NUCLEAR-MASS; SHAPE ISOMER; DRIP-LINE; FISSION; DECAY; SUPERSHELLS; CLUSTERS; STATES AB Recent and planned experiments aiming at the observation of the direct links between superdeformed and normal-deformed structures in the A similar to 190 mass region may offer unique information on the absolute nuclear binding energy in the 2:1 minima, and hence on the magnitude of shell effects in the superdeformed well. In the present paper, the self-consistent mean-field theory with density-dependent pairing interaction is used to explain at the same time the two-particle separation energies in the first and second wells, and the excitation energies of superdeformed states in the A similar to 190 and A similar to 240 mass regions. [S0556-2813(98)03404-9]. C1 ULB, Serv Phys Nucl Theor, B-1050 Brussels, Belgium. Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. Univ Warsaw, Inst Theoret Phys, PL-00681 Warsaw, Poland. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Ctr Etud Saclay, Serv Phys Theor, F-91191 Gif Sur Yvette, France. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Heenen, PH (reprint author), ULB, Serv Phys Nucl Theor, CP 229, B-1050 Brussels, Belgium. NR 48 TC 27 Z9 27 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 1719 EP 1726 DI 10.1103/PhysRevC.57.1719 PG 8 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700021 ER PT J AU Kaneko, K Zhang, JY AF Kaneko, K Zhang, JY TI Cranking model with proton-neutron correlations SO PHYSICAL REVIEW C LA English DT Article ID HIGH-SPIN STATES; SIGNATURE INVERSION; ODD NUCLEI; TRIAXIALITY AB A cranking Hartree-Fock-BCS HFB model with T=0 and T=1 proton-neutron correlations is proposed and discussed. Numerical calculations are carried out on a single (g(9/2))(p)(g(9/2))(n) Shell as a first practical try. It is found that the T=0 proton-neutron pairing correlation is crucial for a crossing of an even-spin ground band by an odd-spin band, a so-called T=1 and T=0 band crossing in an N=Z odd-odd system. A conventional spin alignment of a ground state band in an even-even system is also examined. A delay of this spin alignment due to a T=1,J=0 proton-neutron pairing correlation is found for nuclei with N=Z. [S0556-2813(98)03504-3]. C1 Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. Kyushu Sangyo Univ, Dept Phys, Fukuoka 813, Japan. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Kaneko, K (reprint author), Oak Ridge Natl Lab, Joint Inst Heavy Ion Res, Oak Ridge, TN 37831 USA. NR 20 TC 31 Z9 31 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 1732 EP 1737 DI 10.1103/PhysRevC.57.1732 PG 6 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700023 ER PT J AU Ogloblin, AA Khoa, DT Kondo, Y Glukhov, YA Dem'yanova, AS Rozhkov, MV Satchler, GR Goncharov, SA AF Ogloblin, AA Khoa, DT Kondo, Y Glukhov, YA Dem'yanova, AS Rozhkov, MV Satchler, GR Goncharov, SA TI Pronounced airy structure in elastic O-16+C-12 scattering at E-lab=132 MeV SO PHYSICAL REVIEW C LA English DT Article ID COUPLED-CHANNELS CALCULATIONS; COLD NUCLEAR-MATTER; O-16+O-16 SYSTEM; FOLDING MODEL; POTENTIALS; O-16 AB Measurement of elastic O-16+C-12 scattering at E-lab=132 MeV has been performed over the angular range 6 degreesheavy and heavy-->light meson transitions are studied as a phenomenological application of a heavy-quark limit of Dyson-Schwinger equations. Employing two parameters, E, the difference between the mass of the heavy meson and the effective mass of the heavy quark, and Lambda, the width of the heavy-meson Bethe-Salpeter amplitude, we calculate f(+)(t) for all decays on their entire kinematically accessible t domain. Our study favors f(B), in the range 0.135-0.17 GeV and with E = 0.44 GeV and 1/Lambda = 0.14 fm we obtain f(+)(B pi)(0)=0.46. As a result of neglecting 1/m(c) corrections, we estimate that our calculated values of rho(2)=0.87 and f(+)(DK)(0)=0.62 are too low by approximately 15%. However, the bulk of these corrections should cancel in our calculated values of Br(D-->pi l nu)/Br(D-->Kl nu)=0.13 and f(+)(D pi)(0)/f(+)(DK)(0)=1.16. C1 Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Dubna 141980, Russia. Joint Inst Nucl Res, Lab Comp Tech & Automat, Dubna 141980, Russia. Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. RP Ivanov, MA (reprint author), Joint Inst Nucl Res, Bogoliubov Lab Theoret Phys, Dubna 141980, Russia. OI Roberts, Craig/0000-0002-2937-1361 NR 48 TC 50 Z9 50 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 1991 EP 2003 DI 10.1103/PhysRevC.57.1991 PG 13 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700051 ER PT J AU Norman, EB Browne, E Chan, YD Goldman, ID Larimer, RM Lesko, KT Nelson, M Wietfeldt, FE Zlimen, I AF Norman, EB Browne, E Chan, YD Goldman, ID Larimer, RM Lesko, KT Nelson, M Wietfeldt, FE Zlimen, I TI Half-life of Ti-44 SO PHYSICAL REVIEW C LA English DT Article ID BI-207; LIVES AB We present the results of two separate measurements of the half-life of Ti-44 relative to those of Na-22 and Bi-207, respectively. By comparing the numbers of 1157-keV gamma rays from Ti-44 to those of 1274-keV gamma rays from Na-22 observed from a mixed source over a period of approximately 2 yr, we determined the half-life of Ti-44 to be 61.5+/-1.0 yr. From an approximately 1-yr-long study of another mixed source, where we compared the numbers of 1157-keV gamma rays from Ti-44 to those of 1064-keV gamma rays from Bi-207, We determined the Ti-44 half-life to be 62+/-5 yr. From these two results, we have obtained a best value of 62+/-2 yr for the half-life of Ti-44. The astrophysical implications of this result are discussed. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Sao Paulo, Inst Fis, BR-01498 Sao Paulo, Brazil. Natl Inst Stand & Technol, Gaithersburg, MD 20899 USA. RP Norman, EB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 35 TC 37 Z9 37 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 2010 EP 2016 DI 10.1103/PhysRevC.57.2010 PG 7 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700053 ER PT J AU Zhang, XQ Hamilton, JH Ramayya, AV Peker, LK Hwang, JK Jones, EF Komicki, J Beyer, CJ Gore, PM Babu, BRS Ginter, TN Asztalos, SJ Chu, SY Gregorich, KE Lee, IY Macchiavelli, AO Macleod, RW Rasmussen, JO Gilat, J Ter-Akopian, GM Oganessian, YT Daniel, AV Ma, WC Varmette, PG Cole, JD Aryaeinejad, R Butler-Moore, K Dardenne, YX Drigert, MW Stoyer, MA Wild, JF Becker, JA Bernstein, LA Lougheed, RW Moody, KJ Donangelo, R Prussin, SG Griffin, HC AF Zhang, XQ Hamilton, JH Ramayya, AV Peker, LK Hwang, JK Jones, EF Komicki, J Beyer, CJ Gore, PM Babu, BRS Ginter, TN Asztalos, SJ Chu, SY Gregorich, KE Lee, IY Macchiavelli, AO Macleod, RW Rasmussen, JO Gilat, J Ter-Akopian, GM Oganessian, YT Daniel, AV Ma, WC Varmette, PG Cole, JD Aryaeinejad, R Butler-Moore, K Dardenne, YX Drigert, MW Stoyer, MA Wild, JF Becker, JA Bernstein, LA Lougheed, RW Moody, KJ Donangelo, R Prussin, SG Griffin, HC TI Identification of new negative-parity levels in Nd-152,Nd-154 SO PHYSICAL REVIEW C LA English DT Article ID OCTUPOLE DEFORMATION; ISOTOPES; BAND AB From an experiment with Gammasphere and a Cf-252 spontaneous fission source, a new negative-parity band in Nd-154 and new negative-parity levels in Nd-152 Were identified and the yrast bands were extended to 18(+) in Nd-154 and 20(+) in Nd-152 in a triple gamma coincidence study. These new negative-parity bands are consistent with octupole vibrational mode. There is a constant difference as a function of spin between the J(1) values for the negative-parity band in Nd-152 and J(1) for the similar negative-parity band in Nd-154, however, their J(2) values are essentially identical. These bands indicate a new kind of identical band. C1 Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Joint Inst Nucl Res, Dubna 141980, Russia. Joint Inst Heavy Ion Res, Oak Ridge, TN 37835 USA. Mississippi State Univ, Dept Phys, Mississippi State, MS 39762 USA. Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Fed Rio de Janeiro, Rio De Janeiro, Brazil. Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Univ Michigan, Ann Arbor, MI 48109 USA. RP Zhang, XQ (reprint author), Vanderbilt Univ, Dept Phys, Nashville, TN 37235 USA. NR 12 TC 12 Z9 12 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 2040 EP 2042 DI 10.1103/PhysRevC.57.2040 PG 3 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700057 ER PT J AU Norman, EB Sur, B AF Norman, EB Sur, B TI Cross sections for the O-17(n,p)N-17 and O-17(n,d)N-16 reactions at 14 MeV SO PHYSICAL REVIEW C LA English DT Article AB We measured the cross sections for the O-17(n,p)N-17 and O-17(n,d)N-16 reactions at a neutron bombarding energy of 14 MeV. A small DT generator was used to produce 14 MeV neutrons which irradiated known mixtures of O-16 and O-17. The resulting N-16 and N-17 activities were transported to a remote counting station where a germanium detector was used to measure the characteristic gamma rays emitted in the beta decays of these isotopes. By using the cross section for the O-16(n,p) reaction as a reference, we determined the cross sections for the O-17(n,p) and O-17(n,d) reactions to be 27.4+/-6.1 and 5.6+/-1.9 mb, respectively. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Atom Energy Canada Ltd, Chalk River Nucl Labs, Chalk River, ON K0J 1J0, Canada. RP Norman, EB (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 6 TC 2 Z9 2 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 2043 EP 2045 DI 10.1103/PhysRevC.57.2043 PG 3 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700058 ER PT J AU Zaerpoor, K Chan, YD DiGregorio, DE Dragowsky, MR Hindi, MM Isaac, MCP Krane, KS Larimer, RM Macchiavelli, AO Macleod, RW Miocinovic, P Norman, EB Robinson, SJ AF Zaerpoor, K Chan, YD DiGregorio, DE Dragowsky, MR Hindi, MM Isaac, MCP Krane, KS Larimer, RM Macchiavelli, AO Macleod, RW Miocinovic, P Norman, EB Robinson, SJ TI Cosmic-ray half-life of Pm-144 SO PHYSICAL REVIEW C LA English DT Article AB In order to test the possibility of using Pm-144 as a clock to measure the mean cosmic-ray confinement time in the Galaxy, we counted a highly purified 1.4 mu Ci source Of this isotope in GAMMASPHERE and searched for its astrophysically interesting beta(+) decay branch through the observation of positron-annihilation gamma rays in coincidence with the characteristic 697-keV gamma ray. Analysis of 57 h of source counting and 15 h of background shows no net signal and results in an upper limit of 3.7 of 511-511-697 keV coincident events. From this result we establish a 90% confidence level upper limit on the branch for this decay mode to be 7.4x10(-6)%. The implications of this result for the Pm-144 cosmic-ray chronometer problem are discussed. C1 Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Comis Nacl Energia Atom, Lab TANDAR, RA-1429 Buenos Aires, DF, Argentina. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Zaerpoor, K (reprint author), Oregon State Univ, Dept Phys, Corvallis, OR 97331 USA. NR 6 TC 1 Z9 1 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP 2046 EP 2048 DI 10.1103/PhysRevC.57.2046 PG 3 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700059 ER PT J AU Casten, RF Wilhelm, M Radermacher, E Zamfir, NV von Brentano, P AF Casten, RF Wilhelm, M Radermacher, E Zamfir, NV von Brentano, P TI The first excited 0(+) state in Sm-152 SO PHYSICAL REVIEW C LA English DT Article AB The properties of K=0(+) excitations in deformed and transitional nuclei have recently been of intense interest. We present results of a study of the deexcitations of the lowest excited 0(+) state in Sm-152 from the epsilon-decay of Eu-152, yielding one of the few precisely known values of the branching ratio R-og(gamma)=B(E2;2(gamma)(+) -->0(2)(+))/B(E2;2(gamma)(+)-->0(1)(+)) =0.048(4), which is extraordinarily small. From T-1/2(2(gamma)(+)) we also obtain B(E2;2(gamma)(+) -->0(2)(+))=0.17 W.u. Values of R-og(gamma) calculated in the interacting boson model (IBA) go to zero extremely rapidly, changing by orders of magnitude for a narrow range of parameter values. Sm-152 is a rare case of a transitional nucleus that lands almost at the minimum. Sm-152 and Gd-154 are the only nuclei from 90 less than or equal to N less than or equal to 114 where the B(E2) values for all four transitions 2(gamma)(+)-->0(2)(+), 2(gamma)(+)-->0(1)(+), 0(2)(+)-->2(1)(+), and 2(1)(+)-->0(1)(+) are now known. In Sm-152 these B(E2) values span three orders of magnitude, from 144 to 0.17 W.u. and are reproduced to within a factor of 2-3 by the IBA. The rather strong B(E2;0(2)(+)-->-2(1)(+)) value of 33 W.u, suggest that the 0(2)(+) level is an example of a good low energy beta-vibration. [S0556-2813(98)50104-5]. C1 Yale Univ, WNSL, New Haven, CT 06520 USA. Univ Cologne, Inst Kernphys, D-5000 Cologne 41, Germany. Brookhaven Natl Lab, Upton, NY 11973 USA. Clark Univ, Worcester, MA 01610 USA. Inst Atom Phys, R-76900 Bucharest, Romania. RP Casten, RF (reprint author), Yale Univ, WNSL, New Haven, CT 06520 USA. RI Zamfir, Nicolae Victor/F-2544-2011 NR 17 TC 52 Z9 52 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP R1553 EP R1557 DI 10.1103/PhysRevC.57.R1553 PG 5 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700001 ER PT J AU Koehler, PE Spencer, RR Guber, KH Winters, RR Raman, S Harvey, JA Hill, NW Blackmon, JC Bardayan, DW Larson, DC Lewis, TA Pierce, DE Smith, MS AF Koehler, PE Spencer, RR Guber, KH Winters, RR Raman, S Harvey, JA Hill, NW Blackmon, JC Bardayan, DW Larson, DC Lewis, TA Pierce, DE Smith, MS TI High resolution neutron capture and transmission measurements on (137)Ba and their impact on the interpretation of meteoric barium anomalies SO PHYSICAL REVIEW C LA English DT Article ID S-PROCESS BA; CROSS-SECTIONS; MURCHISON METEORITE; SIC GRAINS; ISOTOPES; STARS AB We have made improved measurements of the neutron capture and total cross sections for (137)Ba over a sufficiently wide range of energies so that the reaction rate at s-process temperatures (kT=6-23 keV) can be determined solely from the data. These rates are crucial for the interpretation of recently discovered anomalies of Ba isotopes in silicon carbide grains from the Murchison meteorite. Recent stellar models of the s process are in agreement with the meteoric anomaly data for Ba only if the (137)Ba(n,gamma) reaction rate is 20% larger than the previously accepted rate. Our reaction rates at s-process temperatures are in agreement with the extrapolated reaction rate from the most recent previous measurement. Hence, our results uphold, and place on much firmer footing, the discrepancy between recent stellar models of the s-process and the meteoric anomaly data.[S0556-2813(98)50304-4]. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Denison Univ, Dept Phys, Granville, OH 43023 USA. Yale Univ, AW Wright Nucl Struct Lab, New Haven, CT 06510 USA. RP Koehler, PE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. NR 23 TC 10 Z9 10 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP R1558 EP R1561 DI 10.1103/PhysRevC.57.R1558 PG 4 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700002 ER PT J AU Stephens, FS Deleplanque, MA Macchiavelli, AO Diamond, RM Fallon, P Lee, IY Schuck, C AF Stephens, FS Deleplanque, MA Macchiavelli, AO Diamond, RM Fallon, P Lee, IY Schuck, C TI Alignment and pseudospin symmetry SO PHYSICAL REVIEW C LA English DT Article AB Pseudospin symmetry has been invoked as a possible explanation for the "quantized alignment" observed in some superdeformed "identical" bands. The dearest case involves the 1/2[301] orbital (a pseudospin singlet, <(Lambda)over tilde>=0), where pseudospin alignment provides an explanation for some identical bands in the mass-150 region. Pseudospin doublets (Omega = <(Lambda)over tilde>+/-1/2) can also generate quantized alignments and such an explanation, with <(Lambda)over tilde>=1, has recently been proposed for the band in Au-191 identical to Hg-192. The present work examine's whether the data on the normally deformed nuclei support such an interpretation and concludes that pseudospin alignment is plausible for states with <(Lambda)over tilde>=0 or 1. [S0556-2813(98)50504-3]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Ctr Spectrometrie Nucl & Spectrometrie Masse, CNRS, IN2P3, F-91405 Orsay, France. RP Stephens, FS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 12 TC 21 Z9 21 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2813 J9 PHYS REV C JI Phys. Rev. C PD APR PY 1998 VL 57 IS 4 BP R1565 EP R1568 DI 10.1103/PhysRevC.57.R1565 PG 4 WC Physics, Nuclear SC Physics GA ZK406 UT WOS:000073317700004 ER PT J AU Bishai, M Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Glenn, S Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Wang, R Zhou, X Toan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Azfar, F Efimov, A Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartel, J Csorna, SE Jain, V McLean, KW Marka, S Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Bliss, DW Masek, G Paar, HP Prell, S Sharma, V Asner, DM Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Ford, WT Gritsan, A Park, H Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Boisvert, V Cassel, DG Cho, HA Crowcroft, DS Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Kim, PC Kreinick, DL Lee, T Liu, Y Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Valant-Spaight, B Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J Brandenburg, G Briere, RA Ershov, A Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, R Kotov, S Kravchenko, I Kwak, N Zhou, L Anderson, S Kubota, Y Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Duboscq, JE Fujino, D Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P AF Bishai, M Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Glenn, S Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Wang, R Zhou, X Toan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Azfar, F Efimov, A Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartel, J Csorna, SE Jain, V McLean, KW Marka, S Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Bliss, DW Masek, G Paar, HP Prell, S Sharma, V Asner, DM Gronberg, J Hill, TS Lange, DJ Morrison, RJ Nelson, HN Nelson, TK Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Ford, WT Gritsan, A Park, H Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Boisvert, V Cassel, DG Cho, HA Crowcroft, DS Dickson, M von Dombrowski, S Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Kim, PC Kreinick, DL Lee, T Liu, Y Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Valant-Spaight, B Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J Brandenburg, G Briere, RA Ershov, A Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, R Kotov, S Kravchenko, I Kwak, N Zhou, L Anderson, S Kubota, Y Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Duboscq, JE Fujino, D Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P TI Search for the decay B -> D-s1(+)(2536)X SO PHYSICAL REVIEW D LA English DT Article ID B->C(C)OVER-BAR-S; MESONS AB We have searched for the decay B-->D-s1(+)(2536)X and measured an upper limit for the inclusive branching fraction of B(B-->(D) over bar(s1)(+)X)<0.96% at the 90% confidence level. This limit is small compared with the total expected B-->(D) over bar(*)D(*)KX rate. Assuming factorization, the D-s1(+) decay constant is constrained to be f(Dsl+)<114 MeV at the 90% confidence level, at least 2.5 times smaller than that of D-s(+). [S0556-2821(98)01809-8]. C1 Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Yonsei Univ, Seoul 120749, South Korea. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Austin, TX 78712 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. BINP, RU-630090 Novosibirsk, Russia. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Montreal, PQ, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. RP Bishai, M (reprint author), Purdue Univ, W Lafayette, IN 47907 USA. RI Briere, Roy/N-7819-2014 OI Briere, Roy/0000-0001-5229-1039 NR 24 TC 9 Z9 9 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 3847 EP 3853 DI 10.1103/PhysRevD.57.3847 PG 7 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400009 ER PT J AU Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mandelkern, M Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Schmid, B Schultz, J Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Standifird, J Stoker, D Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA AF Bai, JZ Bian, JG Blum, I Chai, ZW Chen, GP Chen, HF Chen, J Chen, JC Chen, Y Chen, YB Chen, YQ Cheng, BS Cui, XZ Ding, HL Ding, LY Dong, LY Du, ZZ Dunwoodie, W Feng, S Gao, CS Gao, ML Gao, SQ Gratton, P Gu, JH Gu, SD Gu, WX Gu, YF Guo, YN Han, SW Han, Y Harris, FA He, J He, JT He, M Hitlin, DG Hu, GY Hu, HM Hu, JL Hu, QH Hu, T Hu, XQ Huang, JD Huang, YZ Izen, JM Jiang, CH Jin, Y Ke, ZJ Kelsey, MH Kim, BK Kong, D Lai, YF Lang, PF Lankford, A Li, CG Li, D Li, HB Li, J Li, PQ Li, RB Li, W Li, WD Li, WG Li, XH Li, XN Liu, HM Liu, J Liu, JH Liu, RG Liu, Y Lou, XC Lowery, B Lu, F Lu, JG Lu, JY Lu, LC Luo, CH Ma, AM Ma, EC Ma, JM Malchow, R Mandelkern, M Mao, HS Mao, ZP Meng, XC Nie, J Olsen, SL Oyang, J Paluselli, D Pan, LJ Panetta, J Porter, F Qi, ND Qi, XR Qian, CD Qiu, JF Qu, YH Que, YK Rong, G Schernau, M Schmid, B Schultz, J Shao, YY Shen, BW Shen, DL Shen, H Shen, XY Sheng, HY Shi, HZ Song, XF Standifird, J Stoker, D Sun, F Sun, HS Tang, SQ Toki, W Tong, GL Wang, F Wang, LS Wang, LZ Wang, M Wang, M Wang, P Wang, PL Wang, SM Wang, TJ Wang, YY Weaver, M Wei, CL Wu, YG Xi, DM Xia, XM Xie, PP Xie, Y Xie, YH Xiong, WJ Xu, CC Xu, GF Xue, ST Yan, J Yan, WG Yang, CM Yang, CY Yang, J Yang, W Yang, XF Ye, MH Ye, SW Ye, YX Yi, K Yu, CS Yu, CX Yu, YH Yu, ZQ Yu, ZT Yuan, CZ Yuan, Y Zhang, BY Zhang, CC Zhang, DH Zhang, DH Zhang, HL Zhang, J Zhang, JL Zhang, JW Zhang, LS Zhang, QJ Zhang, SQ Zhang, XY Zhang, Y Zhang, YY Zhao, DX Zhao, HW Zhao, JW Zhao, M Zhao, WR Zheng, JP Zheng, LS Zheng, ZP Zhou, GP Zhou, HS Zhou, L Zhu, QM Zhu, YC Zhu, YS Zhuang, BA TI Search for psi(2S) production in e(+)e(-) annihilations at 4.03 GeV SO PHYSICAL REVIEW D LA English DT Article ID DECAY AB A search is performed for the production of the psi(2S) in e(+)e(-) annihilation at a center-of-mass energy of 4.03 GeV using the BES detector operated at the Beijing Electron Positron Collider (BEPC). The kinematic features of the reconstructed psi(2S) signal are consistent with its being produced only in association with an energetic photon resulting from initial state radiation (ISR). Limits are placed on psi(2S) production from the decay of unknown charmonia or metastable hybrids that might be produced in e(+)e(-) annihilations at 4.03 GeV. Under the assumption that the observed cross section for psi(2S) production is due entirely to ISR, the partial width Gamma(ee) of the psi(2S) is measured to be 2.07+/-0.32 keV. [S0556-2821(98)01309-5]. C1 Inst High Energy Phys, Beijing 100039, Peoples R China. CALTECH, Pasadena, CA 91125 USA. Colorado State Univ, Ft Collins, CO 80523 USA. Hangzhou Univ, Hangzhou 310028, Peoples R China. Shandong Univ, Jinan 250100, Peoples R China. Shanghai Jiao Tong Univ, Shanghai 200030, Peoples R China. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Calif Irvine, Irvine, CA 92717 USA. Univ Sci & Technol China, Anhua 230026, Peoples R China. Univ Texas, Richardson, TX 75083 USA. RP Bai, JZ (reprint author), Inst High Energy Phys, Beijing 100039, Peoples R China. RI Chen, Yu/E-3788-2012; Lu, Lanchun/E-3551-2011; dong, liaoyuan/A-5093-2015; OI Yuan, Chang-Zheng/0000-0002-1652-6686; dong, liaoyuan/0000-0002-4773-5050; Li, Xiaonan/0000-0003-2857-0219 NR 12 TC 14 Z9 15 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 3854 EP 3859 DI 10.1103/PhysRevD.57.3854 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400010 ER PT J AU Abele, A Bischoff, S Blum, P Djaoshvili, N Engelhardt, D Herbstrith, A Holtzhaussen, C Tischhauser, M Adomeit, J Kammle, B Meier, J Schmidt, P Seibert, R Strohbusch, U Amsler, C von Dombrowski, S Giarritta, P Heinzelmann, M Ould-Saada, F Pietra, C Regenfus, C Spanier, S Baker, CA Batty, CJ Pinder, CN Barnett, BM Crede, V Ehmanns, A Herz, M Kalinowsky, H Klempt, E Pick, B Resag, S Strassburger, C Thoma, U Wittmack, K Benayoun, M Berdoz, A McCrady, R Meyer, CA Beuchert, K Degner, T Koch, H Kunze, M Kurilla, U Ludemann, J Matthay, H Peters, K Ratajczak, M Stock, H Braune, K Cramer, O Dunnweber, W Faessler, MA Hessey, NP Jamnik, D Kolo, C Roethel, W Volcker, C Wallis, S Walther, D Wiedner, U Zupancic, C Case, T Crowe, KM Heinsius, FH Kammel, P Lakata, M Doser, M Kisiel, J Landua, R Montanet, L Ouared, R Haddock, RP Hidas, P Suffert, M AF Abele, A Bischoff, S Blum, P Djaoshvili, N Engelhardt, D Herbstrith, A Holtzhaussen, C Tischhauser, M Adomeit, J Kammle, B Meier, J Schmidt, P Seibert, R Strohbusch, U Amsler, C von Dombrowski, S Giarritta, P Heinzelmann, M Ould-Saada, F Pietra, C Regenfus, C Spanier, S Baker, CA Batty, CJ Pinder, CN Barnett, BM Crede, V Ehmanns, A Herz, M Kalinowsky, H Klempt, E Pick, B Resag, S Strassburger, C Thoma, U Wittmack, K Benayoun, M Berdoz, A McCrady, R Meyer, CA Beuchert, K Degner, T Koch, H Kunze, M Kurilla, U Ludemann, J Matthay, H Peters, K Ratajczak, M Stock, H Braune, K Cramer, O Dunnweber, W Faessler, MA Hessey, NP Jamnik, D Kolo, C Roethel, W Volcker, C Wallis, S Walther, D Wiedner, U Zupancic, C Case, T Crowe, KM Heinsius, FH Kammel, P Lakata, M Doser, M Kisiel, J Landua, R Montanet, L Ouared, R Haddock, RP Hidas, P Suffert, M TI (p)over-bar-p annihilation at rest into KLK +/-pi(-/+) SO PHYSICAL REVIEW D LA English DT Article ID COUPLED-CHANNEL ANALYSIS; F(0)(1500) DECAY; SCALAR GLUEBALL; HIGH-STATISTICS; RESONANCE; THRESHOLD; PARTICLES; ETA AB We present a measurement and partial wave analysis of the final state K(L)K(+/-)pi(-/+) of (p) over bar p annihilation at rest in liquid hydrogen. This reaction is important for the study of the KK decay mode of scalar resonances, in particular, the isovectors a(0)(980) and a(0)(1450). The determination of the a(0)(1450) production also fixes the (K) over bar K coupling of the isoscalar f(0)(1500) which is discussed as a glueball. We find B((p) over bar p -->a(0)(1450)pi;a(0)(1450)-->(K) over bar K)=(8.88+/-1.68) X 10(-4) and hence B((p) over bar p-->f(0)(1500)pi;f(0)(1500)-->(K) over bar K)=(4.52 +/- 0.36) x 10(-4). The mass and width of a(0)(1450) are m = 1480+/-30 MeV/c(2) and Gamma = 265+/-15 MeV/c(2), respectively. For a(0)(980) we determine the relative ratio B((p) over bar p-->a(0) pi;a(0)-->(K) over bar K)/B((p) over bar p-->a(0) pi;a(0)-->pi eta)=0.23+/-0.05 and its relative coupling, (K) over bar K to pi eta, is 1.03+/-0.14. [S0556-2821(98)02907-5]. C1 Univ Karlsruhe, D-76021 Karlsruhe, Germany. Univ Hamburg, D-22761 Hamburg, Germany. Univ Zurich, CH-8057 Zurich, Switzerland. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Bonn, D-53115 Bonn, Germany. LPNHE Paris 6, F-75252 Paris, France. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Univ Bochum, D-44780 Bochum, Germany. Univ Munich, D-80333 Munich, Germany. Univ Calif Berkeley, LBNL, Berkeley, CA 94720 USA. CERN, CH-1211 Geneva 4, Switzerland. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Hungarian Acad Sci, H-1525 Budapest, Hungary. Ctr Rech Nucl, F-67037 Strasbourg, France. Univ Ljubljana, Ljubljana, Slovenia. RP Univ Karlsruhe, D-76021 Karlsruhe, Germany. NR 37 TC 86 Z9 87 U1 0 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 3860 EP 3872 DI 10.1103/PhysRevD.57.3860 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400011 ER PT J AU Bardeen, W Duncan, A Eichten, E Thacker, H AF Bardeen, W Duncan, A Eichten, E Thacker, H TI Quenched approximation artifacts: A study in two-dimensional QED SO PHYSICAL REVIEW D LA English DT Article ID CHIRAL LOGARITHMS; LATTICE; FERMIONS; QCD; THEOREM AB The spectral properties of the Wilson-Dirac operator in 2-dimensional QED responsible for the appearance of exceptional configurations in quenched simulations are studied in detail. The mass singularity structure of the quenched functional integral is shown to be extremely complicated, with multiple branch points and cuts. The connection of lattice topological charge and exactly real eigenmodes is explored using cooling techniques. The lattice volume and spacing dependence of these modes is studied, as is the effect of clover improvement of the action. A recently proposed modified quenched approximation is applied to the study of meson correlators, and the results compared with both naive quenched and full dynamical calculations of the same quantity. [S0056-2821(98)02507-7]. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15620 USA. Univ Virginia, Dept Phys, Charlottesville, VA 22901 USA. RP Fermilab Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 17 TC 17 Z9 17 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 3890 EP 3901 DI 10.1103/PhysRevD.57.3890 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400013 ER PT J AU Isgur, N AF Isgur, N TI Spin-orbit inversion of excited heavy quark mesons SO PHYSICAL REVIEW D LA English DT Article ID ZWEIG-IIZUKA RULE; SEMILEPTONIC DECAYS; OZI RULE; MODEL; HADRONS; CHROMODYNAMICS; APPROXIMATION; SPECTROSCOPY; TRANSITIONS; SYMMETRY AB The mesonic heavy quark spin multiplets with s(l)(pi l) = 1/2(+) and 3/2(+) are expected to be the lowest-lying excitations above the pseudoscaler and vector ground states with s(l)(pi l) = 1/2(-). I show that for charm and bottom these multiplets are probably inverted, with the 2(+) and 1(+) states with s(l)(pi l) = 3/2(+) about 150 MeV below the 1(+) and 0(+) states with s(l)(pi l) = 1/2(+). If verified, such an inversion would both support the expectation that confinement has no dynamical spin-dependence and indicate that heavy-and light-quark systems may be characterized by the same effective low-energy degrees of freedom. As an important by-product, this work establishes the dynamics of the strange quark as a critical link between heavy-and Light-quark hadrons, justifying efforts toward a much more complete experimental and theoretical understanding of strange mesons and baryons and of strange quarkonia. [S0556-2821(98)00505-0]. C1 Jefferson Lab, Newport News, VA 23606 USA. RP Isgur, N (reprint author), Jefferson Lab, 12000 Jefferson Ave, Newport News, VA 23606 USA. NR 67 TC 66 Z9 66 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4041 EP 4053 DI 10.1103/PhysRevD.57.4041 PG 13 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400028 ER PT J AU Schaffner-Bielich, J Vischer, AP AF Schaffner-Bielich, J Vischer, AP TI Charmlets SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-ION COLLISIONS; QUARK-MATTER DROPLETS; BOTTOM PRODUCTION; CHARMED BARYONS; BAG MODEL; STRANGE; HADRONS; STATES; SEARCH; TETRAQUARKS AB We discuss the possibility that multiply charmed exotics are produced in ultrarelativistic heavy ion collisions. Production probabilities at BNL RHIC are estimated and found to be large enough to allow for the possible detection of single and double charmed exotics. We demonstrate that charm matter is bound due to an attractive one-gluon exchange potential. Furthermore, we study the color magnetic and color electric potential separately, as well as the group structure of such exotics, and estimate their masses. [S0556-2821(98)04807-3]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Niels Bohr Inst, DK-2100 Copenhagen O, Denmark. RP Schaffner-Bielich, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 35 TC 18 Z9 18 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4142 EP 4153 DI 10.1103/PhysRevD.57.4142 PG 12 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400040 ER PT J AU Capstick, S Roberts, W AF Capstick, S Roberts, W TI New baryons in the delta eta and Delta omega channels SO PHYSICAL REVIEW D LA English DT Article ID PAIR-CREATION MODEL; RELATIVIZED QUARK-MODEL; HYPERFINE INTERACTIONS; PI-N; DECAYS; AMPLITUDES; CHROMODYNAMICS; RESONANCES; PHOTOPRODUCTION; BREAKING AB The decays of excited nonstrange baryons into the final states Delta eta and Delta omega are examined in a relativized quark pair creation model. The wave functions and parameters of the model are fixed by previous calculations of N pi and N pi pi, etc., decays through various quasi-two-body channels including N eta and N omega. Our results show that the combination of thresholds just below the region of interest and the isospin selectivity of these channels should allow the confirmation of several weakly established Delta baryons and the discovery of new Delta baryons in pion and photoproduction of these final states. [S0556-2821(98)01609-9]. C1 Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. Old Dominion Univ, Dept Phys, Norfolk, VA 23529 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Florida State Univ, Supercomp Computat Res Inst, Tallahassee, FL 32306 USA. NR 36 TC 32 Z9 32 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4301 EP 4309 DI 10.1103/PhysRevD.57.4301 PG 9 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400055 ER PT J AU Giele, WT Keller, S AF Giele, WT Keller, S TI Determination of W-boson properties at hadron colliders SO PHYSICAL REVIEW D LA English DT Article ID YAN CROSS-SECTION; = 1.8 TEV; HIGH-PT W; TRANSVERSE-MOMENTUM; PBARP COLLISIONS; K-FACTOR; ORDER; MASS; WIDTH AB Methods for measuring the W-boson properties at hadron colliders are discussed. It is demonstrated that the ratio between the W- and Z-boson observables can be reliably calculated using fixed order perturbative QCD, even when the individual W- and Z-boson observables are not. Hence, by using a measured Z-boson observable and the perturbative calculation of the ratio of the W- over Z-boson observable, we can accurately predict the W-boson observable. The use of the ratio reduces both the experimental and theoretical systematic uncertainties substantially. Compared to the currently used methods it might, at high luminosity, result in a smaller overall uncertainty on the measured W-boson mass and width. [S0556-2821(98)00509-8]. C1 Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Giele, WT (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 35 TC 22 Z9 22 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4433 EP 4440 DI 10.1103/PhysRevD.57.4433 PG 8 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400071 ER PT J AU Perl, ML AF Perl, ML TI New method for searching for massive, stable, charged elementary particles SO PHYSICAL REVIEW D LA English DT Article AB I describe a new method of searching for electrically charged and stable elementary particles with masses larger than about 10(13) GeV/c(2). This method is based on measuring the terminal velocity of uniform radius liquid drops falling in air. The range of this search method and concomitant imponderables are discussed. [S0556-2821(98)03007-0]. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Perl, ML (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 8 TC 2 Z9 2 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4441 EP 4445 DI 10.1103/PhysRevD.57.4441 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400072 ER PT J AU Baer, H Wells, JD AF Baer, H Wells, JD TI Trilepton Higgs boson signal at hadron colliders SO PHYSICAL REVIEW D LA English DT Article ID INTERMEDIATE-MASS HIGGS; FERMILAB TEVATRON; CERN LHC; SUPERCOLLIDERS; SUPERSYMMETRY; H->B(B)OVER-BAR; DECAYS AB Most Higgs boson searches pursued at hadron colliders require Yukawa interactions either in the production or the decay of a Higgs boson. We propose a trilepton Higgs boson search based only upon the gauge interactions of the Higgs boson. This strategy can be utilized successfully for the standard model (SM) Higgs boson as well as nonstandard Higgs bosons which break electroweak symmetry but have little to do with fermion mass generation. The trileptons come from Wh production followed by Wh-->WWW(*)-->3l decays. A SM Higgs trilepton signal would be difficult to detect at the Fermilab Tevatron collider: with 100 fb(-1) of data, only a 3 sigma signal above background can be achieved after cuts if 140 GeV p(K)over-bar-n(pi) SO PHYSICAL REVIEW D LA English DT Article ID DELTA-C+; PARTICLES AB Using data recorded by the CLEO-II detector at CESR, we report new measurements of the branching fractions for the decays of the charmed baryon Lambda(c)(+) into pK(-)pi(+)pi(0), p (K) over bar(0), p (K) over bar(0) pi(+)pi(-) and p (K) over bar(0) pi(0), all measured relative to pK(-)pi(+). The relative branching fractions are 0.67+/-0.04+/-0.11,0.46+/-0.02+/-0.04,0.52+/-0.04+/-0.05, and 0.66+/-0.05+/-0.07, respectively. [S0556-2821(98)05705-1]. C1 SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. BINP, RU-630090 Novosibirsk, Russia. Yonsei Univ, Seoul 120749, South Korea. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Austin, TX 78712 USA. Univ Illinois, Urbana, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Montreal, PQ, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. RP Alam, MS (reprint author), SUNY Albany, Albany, NY 12222 USA. RI Briere, Roy/N-7819-2014 OI Briere, Roy/0000-0001-5229-1039 NR 7 TC 5 Z9 5 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP 4467 EP 4470 DI 10.1103/PhysRevD.57.4467 PG 4 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400076 ER PT J AU Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amidi, E Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, H Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, M Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, J Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lan, H Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Schaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amidi, E Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, H Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, M Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, J Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lan, H Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Schaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A TI Z gamma production in p(p)over-bar collisions at root s=1.8 TeV and limits on anomalous ZZ gamma and Z gamma gamma couplings SO PHYSICAL REVIEW D LA English DT Article ID BOSON AB We present a study of Z gamma+X production in collisions at root s=1.8 TeV from 97 (87) pb(-1) of data collected in the ee gamma (mu mu gamma) decay channel with the D0 detector at Fermilab. The event yield and kinematic characteristics are consistent with the standard model predictions. We obtain limits on anomalous ZZ gamma and Z gamma gamma couplings for form factor scales Lambda=500 GeV and Lambda=750 GeV. Combining this analysis with our previous results yields 95% C.L. limits \h(30)(Z)\<0.36, \h(40)(Z)\<0.05, \h(30)(gamma)\<0.37, and \h(40)(gamma)\<0.05 for a form factor scale Lambda = 750 GeV. [S0556-2821(98)50507-3]. C1 NYU, New York, NY 10003 USA. Univ Los Andes, Bogota, Colombia. Univ Arizona, Tucson, AZ 85721 USA. Boston Univ, Boston, MA 02215 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Brown Univ, Providence, RI 02912 USA. Univ Buenos Aires, Buenos Aires, DF, Argentina. Univ Calif Davis, Livermore, CA 95616 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. CINVESTAV, Mexico City 14000, DF, Mexico. Columbia Univ, New York, NY 10027 USA. Univ Delhi, Delhi 110007, India. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Illinois, Chicago, IL 60607 USA. Indiana Univ, Bloomington, IN 47405 USA. Iowa State Univ, Ames, IA 50011 USA. Korea Univ, Seoul, South Korea. Kyungsung Univ, Pusan 608736, South Korea. Inst Nucl Phys, Krakow, Poland. Univ Calif Berkeley, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Moscow State Univ, Moscow, Russia. Univ Nebraska, Lincoln, NE 68588 USA. Northeastern Univ, Boston, MA 02115 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Oklahoma, Norman, OK 73019 USA. Panjab Univ, Chandigarh 160014, India. Inst High Energy Phys, Protvino 142284, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77005 USA. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Univ Rochester, Rochester, NY 14627 USA. CE Saclay, CEA, DAPNIA, Serv Phys Particules, Gif Sur Yvette, France. Seoul Natl Univ, Seoul, South Korea. SUNY Stony Brook, Stony Brook, NY 11794 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. Univ San Francisco Quito, Quito, Ecuador. IHEP, Beijing, Peoples R China. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Belyaev, Alexander/F-6637-2015; Aihara, Hiroaki/F-3854-2010; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Roe, Natalie/A-8798-2012; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Klyukhin, Vyacheslav/D-6850-2012; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016 OI Belyaev, Alexander/0000-0002-1733-4408; Aihara, Hiroaki/0000-0002-1907-5964; Dudko, Lev/0000-0002-4462-3192; Klyukhin, Vyacheslav/0000-0002-8577-6531; De, Kaushik/0000-0002-5647-4489; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108 NR 17 TC 14 Z9 14 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP R3817 EP R3821 DI 10.1103/PhysRevD.57.R3817 PG 5 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400002 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Pani, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, C Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Busk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Pani, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, C Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S TI Search for the decays B-d(0)->mu(+)mu(-) and B-s(0)->mu(+)mu(-) in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW D LA English DT Article ID B-MESON DECAYS; COLLIDER; DETECTOR AB We present a search for the flavor-changing neutral current decays B-d(0)-->mu(+)mu(-) and B-s(0)-->mu(+)mu(-) in collisions at root s=1.8 TeV, using 98 pb(-1) of data collected at the Collider Detector at Fermilab. We find one candidate event for these decays, which is consistent with the background estimates, and set upper limits on the branching fractions of B(B-d(0)-->mu(+)mu(-))<8.6X10(-7) and B(B-s(0)-->mu(+)mu(-))<2.6X10(-6) at 95% confidence level. [S0556-2821(98)50207-X]. C1 Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, Sez Padova, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 19 TC 46 Z9 46 U1 0 U2 1 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 2470-0010 EI 2470-0029 J9 PHYS REV D JI Phys. Rev. D PD APR 1 PY 1998 VL 57 IS 7 BP R3811 EP R3816 DI 10.1103/PhysRevD.57.R3811 PG 6 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZF267 UT WOS:000072880400001 ER PT J AU Hoover, WG Boercker, K Posch, HA AF Hoover, WG Boercker, K Posch, HA TI Large-system hydrodynamic limit for color conductivity in two dimensions SO PHYSICAL REVIEW E LA English DT Article ID INSTABILITY AB Nonequilibrium simulations of two-dimensional shear how have shown that the viscosity is well defined in the large-system "hydrodynamic" limit. Those simulations, with up to a quarter million particles, were carried out at fixed energy and strain rate. Here we explore the mass current response to an external "color field" E for N particles, half with "color charge" +1, and half with -1. The fixed-field large-N "color conductivity" kappa equivalent to[+/-upsilon/E], with the energy per particle held constant, likewise indicates a well-defined large-system limit at moderate fields. C1 Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Vienna, Inst Expt Phys, A-1090 Vienna, Austria. RP Hoover, WG (reprint author), Univ Calif Davis, Dept Appl Sci, Livermore, CA 94551 USA. NR 12 TC 19 Z9 19 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 1998 VL 57 IS 4 BP 3911 EP 3916 DI 10.1103/PhysRevE.57.3911 PG 6 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZH084 UT WOS:000073070500034 ER PT J AU Ritchie, B Decker, CD AF Ritchie, B Decker, CD TI Propagation of an ultrashort, intense laser pulse in a relativistic plasma SO PHYSICAL REVIEW E LA English DT Article ID UNDERDENSE PLASMAS; ACCELERATION AB A Maxwell-relativistic fluid model is developed for the propagation of an ultrashort, intense laser pulse through an underdense plasma. The separability of plasma and optical frequencies (omega(p) and omega, respectively) for small omega(p)/omega is not assumed; thus the validity of multiple-scales theory (MST) can be tested. The theory is valid when omega(p)/omega is of order unity or for cases in which omega(p)/omega much less than 1 but strongly relativistic motion causes higher-order plasma harmonics to be generated which overlap the region of the first-order laser harmonic, such that MST would not be expected to be valid, although its principal validity criterion omega(p)/omega much less than 1 holds. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Ritchie, B (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 25 TC 6 Z9 6 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 1998 VL 57 IS 4 BP 4645 EP 4649 DI 10.1103/PhysRevE.57.4645 PG 5 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZH084 UT WOS:000073070500108 ER PT J AU Woolsey, NC Hammel, BA Keane, CJ Back, CA Moreno, JC Nash, JK Calisti, A Mosse, C Stamm, R Talin, B Asfaw, A Klein, LS Lee, RW AF Woolsey, NC Hammel, BA Keane, CJ Back, CA Moreno, JC Nash, JK Calisti, A Mosse, C Stamm, R Talin, B Asfaw, A Klein, LS Lee, RW TI Competing effects of collisional ionization and radiative cooling in inertially confined plasmas SO PHYSICAL REVIEW E LA English DT Article ID RAY SPECTROSCOPIC MEASUREMENTS; K-SHELL; NEUTRON SPECTROSCOPY; DETECTOR ARRAY; DENSE-PLASMAS; FUSION; MODEL; SPECTRA; NOVA; TEMPERATURES AB We describe an experimental investigation, a detailed analysis of the Ar XVII 1s(2 1)S-1s3p P-1 (He beta) line shape formed in a high-energy-density implosion, and report on one-dimensional radiation-hydrodynamics simulation of the implosion. In this experiment trace quantities of argon are doped into a lower-Z gas-filled core of a plastic microsphere. The dopant level is controlled to ensure that the He beta transition is optically thin and easily observable. Then the observed line shape is used to derive electron temperatures (T-e) and electron densities (n(e)). The high-energy density plasma, with T-e approaching 1 keV and n(e) = 10(24) cm(-3), is created by placing the microsphere in a gold cylindrical enclosure, the interior of which is directly irradiated by a high-energy laser; the x rays produced by this laser-gold interaction indirectly implode the microsphere. Central to the interpretation of the hydrodynamics of the implosions is the characterization and understanding of the formation of these plasmas. To develop an understanding of the plasma and its temporal evolution, time-resolved T-e and n(e) measurements are extracted using techniques that are independent of the plasma hydrodynamics. Comparing spectroscopic diagnostics with measurements derived from other diagnostic methods, we find the spectroscopic measurements to be reliable and further we find that the experiment-to-experiment comparison shows that these implosions are reproducible. C1 Queens Univ Belfast, Sch Math & Phys, Belfast BT7 1NN, Antrim, North Ireland. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Aix Marseille 1, Ctr St Jerome, PIIM, URA 773, F-13397 Marseille, France. Howard Univ, Dept Phys, Washington, DC 20059 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Woolsey, NC (reprint author), Queens Univ Belfast, Sch Math & Phys, Belfast BT7 1NN, Antrim, North Ireland. EM n.woolsey@qub.ac.uk OI Calisti, Annette/0000-0001-6727-9286 NR 50 TC 52 Z9 52 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 1998 VL 57 IS 4 BP 4650 EP 4662 DI 10.1103/PhysRevE.57.4650 PG 13 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZH084 UT WOS:000073070500109 ER PT J AU Magelssen, GR Delamater, ND Lindman, EL Hauer, AA AF Magelssen, GR Delamater, ND Lindman, EL Hauer, AA TI Measurements of early time radiation asymmetry in vacuum and methane-filled Hohlraums with the reemission ball technique SO PHYSICAL REVIEW E LA English DT Article ID SYMMETRY; NOVA; TARGETS AB In a previous paper [Phys. Rev. E 53, 5240 (1996)], we presented experimental results of a technique for measuring time resolved symmetry in vacuum Hohlraums irradiated with the laser beams from the NOVA laser located at Lawrence Livermore National Laboratory. The experimental method involved x-ray imaging a high-Z ball placed in the center of a laser irradiated vacuum Hohlraum. The signal from the high-Z ball was measured along the Hohlraum axis, and compared with calculations. In this paper, using this experimental technique, we present time-dependent reemission measurements and calculations of the drive symmetry in vacuum and methane-filled Hohlraums for a shaped laser pulse. We also present a method for determining the time dependence of the radiation flux from the measured reemission signal ratios, and do a modal analysis to determine the values of the dominant Legendre components. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Magelssen, GR (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 33 TC 13 Z9 16 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 1998 VL 57 IS 4 BP 4663 EP 4672 DI 10.1103/PhysRevE.57.4663 PG 10 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZH084 UT WOS:000073070500110 ER PT J AU Byrd, JM Cheng, WH Zimmermann, F AF Byrd, JM Cheng, WH Zimmermann, F TI Nonlinear effects of phase modulation in an electron storage ring SO PHYSICAL REVIEW E LA English DT Article ID SYNCHROTRON MOTION AB We present results of experimental studies of the nonlinear dynamics of synchrotron oscillations in the presence of phase modulation in an electron storage ring. A streak camera is used to observe the longitudinal distribution of an electron bunch directly as it forms two stable resonant islands. The positions of the fixed points as a function of modulation frequency agree well with theory. We also present measurements of the diffusion rate from one stable island to the ether for a fixed modulation frequency, which show agreement with the diffusion rates expected from large-angle intrabeam (Touschek) scattering. These results also explain anomalous results of beam transfer function diagnostic measurements obtained at other electron storage rings. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Byrd, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, 1 Cyclotron Rd, Berkeley, CA 94720 USA. NR 15 TC 8 Z9 8 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1063-651X J9 PHYS REV E JI Phys. Rev. E PD APR PY 1998 VL 57 IS 4 BP 4706 EP 4712 DI 10.1103/PhysRevE.57.4706 PG 7 WC Physics, Fluids & Plasmas; Physics, Mathematical SC Physics GA ZH084 UT WOS:000073070500115 ER PT J AU Saha, SK Jain, H Goldstein, JI Miller, AC Brow, RK AF Saha, SK Jain, H Goldstein, JI Miller, AC Brow, RK TI Reaction between titanium and B2O3 melt/glass SO PHYSICS AND CHEMISTRY OF GLASSES LA English DT Article AB Reaction between Ti metal and B2O3 is investigated using x-ray, photoelectron spectroscopy, scanning electron microscopy and wavelength dispersive spectrometry mapping techniques because titanium-to-berate glass seals have great potential for use in biomedical and aerospace applications Immediately after the deposition of a 3 nm thick titanium film under UHV conditions on in situ fractured B2O3 at room temperature, TiBx Ti-O-B and Ti-O-Ti linkages are formed. The fallowing initial reaction occurs at the Ti-B2O3 interface Ti+xB(2)O(3)-->TiB2x-2+B2O3-y+(1/2)(y+3+-3)O-2 In situ heating of the film leads to the incorporation of released oxygen in both the product TiBx layer and the titanium film. TiBx precipitates are formed on the titanium side of diffusion couples prepared at 1000 degrees C. The implications of these results for glass-to-metal adherence are discussed. C1 Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. Univ Massachusetts, Dept Mech Engn, Amherst, MA USA. Lehigh Univ, Zettlemoyer Ctr Surface Studies, Bethlehem, PA 18015 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Jain, H (reprint author), Lehigh Univ, Dept Mat Sci & Engn, Bethlehem, PA 18015 USA. NR 13 TC 3 Z9 3 U1 0 U2 2 PU SOC GLASS TECHNOLOGY PI SHEFFIELD PA THORNTON 20 HALLAM GATE ROAD, SHEFFIELD, S YORKSHIRE, ENGLAND S10 5BT SN 0031-9090 J9 PHYS CHEM GLASSES JI Phys. Chem. Glasses PD APR PY 1998 VL 39 IS 2 BP 118 EP 121 PG 4 WC Chemistry, Physical; Materials Science, Ceramics SC Chemistry; Materials Science GA ZM796 UT WOS:000073576700010 ER PT J AU Noo, F Clack, R White, TA Roney, TJ AF Noo, F Clack, R White, TA Roney, TJ TI The dual-ellipse cross vertex path for exact reconstruction of long objects in cone-beam tomography SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article; Proceedings Paper CT 4th International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine CY JUN 25-28, 1997 CL NEMACOLIN WOODLANDS CONF CTR, LAUREL HIGHLANDS, PENNSYLVANIA HO NEMACOLIN WOODLANDS CONF CTR ID ALGORITHM; ORBITS AB We investigate the way data are used in the algorithm proposed by Kudo and Saito for the exact reconstruction of long objects from axially truncated cone-beam projections. Specifically, we show that the algorithm wastes a large part of the data. To overcome the problem we propose to use a vertex path consisting of two crossing ellipses, for which we devised a new reconstruction algorithm, called the cross algorithm, which does not waste data and is still suitable to exactly handle axial truncation. Results of reconstruction are presented on simulated data and real data from an experimental scanner. C1 Univ Liege, Dept Math Appl, Inst Elect Montefiore, B-4000 Liege, Belgium. Univ Utah, Dept Radiol, Salt Lake City, UT 84132 USA. Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83245 USA. RP Noo, F (reprint author), Univ Liege, Dept Math Appl, Inst Elect Montefiore, B28, B-4000 Liege, Belgium. NR 22 TC 18 Z9 19 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD APR PY 1998 VL 43 IS 4 BP 797 EP 810 DI 10.1088/0031-9155/43/4/009 PG 14 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA ZH069 UT WOS:000073069000009 PM 9572505 ER PT J AU Huesman, RH Reutter, BW Zeng, GL Gullberg, GT AF Huesman, RH Reutter, BW Zeng, GL Gullberg, GT TI Kinetic parameter estimation from SPECT cone-beam projection measurements SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article; Proceedings Paper CT 4th International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine CY JUN 25-28, 1997 CL NEMACOLIN WOODLANDS CONF CTR, LAUREL HIGHLANDS, PENNSYLVANIA HO NEMACOLIN WOODLANDS CONF CTR ID OF-INTEREST EVALUATION; MODEL-BASED ESTIMATION; EMISSION TOMOGRAPHY; COMPUTED-TOMOGRAPHY; ALGORITHM; RECONSTRUCTION AB Kinetic parameters are commonly estimated from dynamically acquired nuclear medicine data, by first reconstructing a dynamic sequence of images and subsequently fitting the parameters to time-activity curves generated from regions of interest overlaid upon the image sequence. Biased estimates can result from images reconstructed using inconsistent projections of a time-varying distribution of radiopharmaceutical acquired by a rotating SPECT system. If the SPECT data are acquired using cone-beam collimators wherein the gantry rotates so that the focal point of the collimators always remains in a plane, additional biases can arise from images reconstructed using insufficient, as well as truncated, projection samples. To overcome these problems we have investigated the estimation of kinetic parameters directly from SPECT cone-beam projection data by modelling the data acquisition process. To accomplish this it was necessary to parametrize the spatial and temporal distribution of the radiopharmaceutical within the SPECT field of view. In a simulated chest image volume, kinetic parameters were estimated for simple one-compartment models for four myocardial regions of interest. Myocardial uptake and washout parameters estimated by conventional analysis of noiseless simulated cone-beam data had biases ranging between 3-26% and 0-28%, respectively. Parameters estimated directly from the noiseless projection data were unbiased as expected, since the model used for fitting was faithful to the simulation. Statistical uncertainties of parameter estimates for 10 000 000 events ranged between 0.2-9% for the uptake parameters and between 0.3-6% for the washout parameters. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. Univ Utah, Dept Radiol, Salt Lake City, UT 84132 USA. RP Huesman, RH (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Ctr Funct Imaging, Berkeley, CA 94720 USA. FU NHLBI NIH HHS [R01-HL50663, P01-HL25840] NR 14 TC 41 Z9 41 U1 2 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD APR PY 1998 VL 43 IS 4 BP 973 EP 982 DI 10.1088/0031-9155/43/4/024 PG 10 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA ZH069 UT WOS:000073069000024 PM 9572520 ER PT J AU Battle, XL Cunningham, GS Hanson, KM AF Battle, XL Cunningham, GS Hanson, KM TI Tomographic reconstruction using 3D deformable models SO PHYSICS IN MEDICINE AND BIOLOGY LA English DT Article; Proceedings Paper CT 4th International Meeting on Fully Three-Dimensional Image Reconstruction in Radiology and Nuclear Medicine CY JUN 25-28, 1997 CL NEMACOLIN WOODLANDS CONF CTR, LAUREL HIGHLANDS, PENNSYLVANIA HO NEMACOLIN WOODLANDS CONF CTR ID PROJECTIONS AB We address the issue of reconstructing the shape of an object with uniform interior activity from a set of projections. We estimate directly from projection data the position of a triangulated surface describing the boundary of the object while incorporating prior knowledge about the unknown shape. This inverse problem is addressed in a Bayesian framework using the maximum a posteriori (MAP) estimate for the reconstruction. The derivatives needed for the gradient-based optimization of the model parameters are obtained using the adjoint differentiation technique. We present results from a numerical simulation of a dynamic cardiac imaging study. A first-pass exam is simulated with a numerical phantom of the right ventricle using the measured system response of the University of Arizona FASTSPECT imager, which consists of 24 detectors. We demonstrate the usefulness of our approach by reconstructing the shape of the ventricle from 10 000 counts. The comparison with an ML-EM result shows the usefulness of the deformable model approach. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hanson, KM (reprint author), Univ Calif Los Alamos Natl Lab, MS-P940, Los Alamos, NM 87545 USA. RI Cunningham, Gregory/F-1017-2011 OI Cunningham, Gregory/0000-0001-8819-4345 NR 23 TC 22 Z9 23 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0031-9155 J9 PHYS MED BIOL JI Phys. Med. Biol. PD APR PY 1998 VL 43 IS 4 BP 983 EP 990 DI 10.1088/0031-9155/43/4/025 PG 8 WC Engineering, Biomedical; Radiology, Nuclear Medicine & Medical Imaging SC Engineering; Radiology, Nuclear Medicine & Medical Imaging GA ZH069 UT WOS:000073069000025 PM 9572521 ER PT J AU Holm, DD Zeitlin, V AF Holm, DD Zeitlin, V TI Hamilton's principle for quasigeostrophic motion SO PHYSICS OF FLUIDS LA English DT Article ID GEOSTROPHIC EQUATIONS; COADJOINT ORBITS; PHASE-SPACE; VARIABLES; MAGNETOHYDRODYNAMICS; HYDRODYNAMICS; GEOMETRY; WAVES AB We show that the equation of quasigeostrophic (QG) potential vorticity conservation in geophysical fluid dynamics follows from Hamilton's principle for stationary variations of an action for geodesic motion in the f-plane case or its prolongation in the beta-plane case. This implies a new momentum equation and an associated Kelvin circulation theorem for QG motion. We treat the barotropic and two-layer baroclinic cases, as well as the continuously stratified case. (C) 1998 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. Univ Paris 06, Meteorol Dynam Lab, F-75252 Paris, France. Univ Cambridge, Isaac Newton Inst Math Sci, Cambridge CB2 1TN, England. RP Holm, DD (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. OI Holm, Darryl D/0000-0001-6362-9912 NR 30 TC 16 Z9 16 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-6631 J9 PHYS FLUIDS JI Phys. Fluids PD APR PY 1998 VL 10 IS 4 BP 800 EP 806 DI 10.1063/1.869623 PG 7 WC Mechanics; Physics, Fluids & Plasmas SC Mechanics; Physics GA ZE096 UT WOS:000072757300005 ER PT J AU Newman, DE Carreras, BA Lopez-Bruna, D Diamond, PH Lebedev, VB AF Newman, DE Carreras, BA Lopez-Bruna, D Diamond, PH Lebedev, VB TI Dynamics and control of internal transport barriers in reversed shear discharges SO PHYSICS OF PLASMAS LA English DT Article ID SELF-ORGANIZED CRITICALITY; DIII-D TOKAMAK; MAGNETIC SHEAR; CONFINEMENT BIFURCATION; ENERGY CONFINEMENT; EDGE TURBULENCE; PLASMA; SIMULATIONS; TFTR; MODE AB Transitions to an enhanced confinement regime in tokamak plasmas with negative central magnetic shear have been observed in a number of devices. A simple model incorporating the nonlinear coupling between the turbulent fluctuations and the sheared radial electric field is added to a transport model in order to investigate the dynamics of the transition to this enhanced confinement mode. In this model, by incorporating; both the instability growth rate profiles and particle and/or power deposition profiles, a rich variety of transition dynamics is uncovered. Transition dynamics and their concomitant thresholds are examined within the context of these models. In the course of investigating these transitions, potential methods for triggering and controlling these enhanced confinement regimes have been discovered and are discussed. (C) 1998 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP Newman, DE (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lopez Bruna, Daniel/L-6539-2014 NR 39 TC 53 Z9 53 U1 2 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 938 EP 952 DI 10.1063/1.872662 PG 15 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600015 ER PT J AU Choe, W Ono, M Hwang, YS Chang, CS AF Choe, W Ono, M Hwang, YS Chang, CS TI Feasibility experiments for electron ripple injection on current drive experiment-upgrade SO PHYSICS OF PLASMAS LA English DT Article ID TOKAMAK; FIELD AB In search of a method to generate a radial electric field in tokamak plasmas, an experimental study has been performed to investigate the possibility of inducing radial electrical current. An external coil array has been used to create a local magnetic ripple well and the electron cyclotron resonance heating (ECH) has been used to trap some electrons that will then be subject to rapid vertical drifts into the plasma. Using a simplified experimental arrangement with only a toroidal magnetic field, an ECH-driven radial electrical current has been observed. The ECH-driven elecron temperature anisotropy, which is necessary for ripple trapping and electron drifts, has been determined by several different methods. The perpendicular temperature can be shown to be as large as 11 times the parallel temperature, which should yield a significant amount of ripple trapping and radial current. (C) 1998 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. Korea Adv Inst Sci & Technol, Taejon 305701, South Korea. NYU, New York, NY USA. RP Choe, W (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Choe, Wonho/C-1556-2011; Hwang, Yong-Seok/D-8347-2012 NR 9 TC 2 Z9 2 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 966 EP 972 DI 10.1063/1.872665 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600018 ER PT J AU Qin, H Tang, WM Rewoldt, G AF Qin, H Tang, WM Rewoldt, G TI Gyrokinetic theory for arbitrary wavelength electromagnetic modes in tokamaks SO PHYSICS OF PLASMAS LA English DT Article ID GUIDING CENTER MOTION; INTERNAL KINK MODES; TOROIDAL PLASMAS; EQUATIONS; INSTABILITIES; EXCITATION AB A linear gyrokinetic system for arbitrary wavelength electromagnetic modes is developed. A wide range of modes in inhomogeneous plasmas, such as the internal kink modes, the toroidal Alfven eigenmode (TAE) modes, and the drift modes, can be recovered from this system. The inclusion of most of the interesting physical factors into a single framework enables one to look at many familiar modes simultaneously, and thus to study the modifications of and the interactions between them in a systematic way. Especially, it is possible to investigate self-consistently the kinetic magnetohydrodynamics (MHD) phenomena entirely from the kinetic side. Phase space Lagrangian Lie perturbation methods and a newly developed computer algebra package for vector analysis in general coordinate system are utilized in the analytical derivation. In tokamak geometries, a two-dimensional finite element code has been developed and tested. In this paper, the basic theoretical formalism and some of the preliminary results are presented. (C) 1998 American Institute of Physics. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Qin, H (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 35 TC 35 Z9 35 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1035 EP 1049 DI 10.1063/1.872633 PG 15 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600026 ER PT J AU Lao, LL La Haye, RJ Burrell, KH Chan, VS Ferron, JR Rettig, CL Rewoldt, G Scoville, JT Staebler, GM Strait, EJ Tang, WM Taylor, TS Wroblewski, D AF Lao, LL La Haye, RJ Burrell, KH Chan, VS Ferron, JR Rettig, CL Rewoldt, G Scoville, JT Staebler, GM Strait, EJ Tang, WM Taylor, TS Wroblewski, D TI Role of ExB flow shear on confinement enhancement in DIII-D high internal inductance discharges with high-confinement edge SO PHYSICS OF PLASMAS LA English DT Article ID REVERSED MAGNETIC SHEAR; D TOKAMAK; ENERGY CONFINEMENT; EQUILIBRIA; TURBULENCE; STABILITY; MODES AB The role of E x B flow shear on confinement enhancement in the DIII-D tokamak [Plasma Physics and Controlled Nuclear Fusion Research, 1986 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] high internal inductance discharges with high-confinement edge is investigated experimentally using a nonaxisymmetric poloidal magnetic-field perturbation from an external coil to drag down the plasma toroidal rotation. At similar values of internal inductance, discharges which rotate faster and have a stronger ExB flow shear have better confinement. These results indicate that ExB flow shear Likely plays an important role in the confinement enhancement of these discharges. (C) 1998 American Institute of Physics. C1 Univ Calif Los Angeles, Los Angeles, CA USA. Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA USA. Gen Atom Co, San Diego, CA 92186 USA. RP Lao, LL (reprint author), Gen Atom Co, POB 85608, San Diego, CA 92186 USA. NR 25 TC 11 Z9 11 U1 1 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1050 EP 1055 DI 10.1063/1.872634 PG 6 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600027 ER PT J AU Skinner, CH Bell, MG Budny, RV Jassby, DL Park, H Ramsey, AT Stotler, DP Strachan, JD AF Skinner, CH Bell, MG Budny, RV Jassby, DL Park, H Ramsey, AT Stotler, DP Strachan, JD TI Transport of recycled deuterium to the plasma core in the Tokamak Fusion Test Reactor SO PHYSICS OF PLASMAS LA English DT Article ID TFTR; CONFINEMENT AB Fueling of the plasma core by recycling in the Tokamak Fusion Test Reactor [Phys. Plasmas 2, 2176 (1995)] has been studied. In plasmas fueled by deuterium recycled from the limiter and tritium-only neutral beam injection, the DT neutron rare provides a measure of the deuterium influx into the core plasma. A reduced influx with plasmas using lithium pellet conditioning: and with plasmas of reduced major (and minor) radius is found. Modeling with the DEGAS [D. P. Stotler et al., Phys. Plasmas 3, 4084 (1996)] neutrals code shows that the dependence on radius can be related to the penetration of neutrals through the scrape-off layer. (C) 1998 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Skinner, CH (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. RI Stotler, Daren/J-9494-2015 OI Stotler, Daren/0000-0001-5521-8718 NR 24 TC 4 Z9 4 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1062 EP 1067 DI 10.1063/1.872636 PG 6 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600029 ER PT J AU Chang, Z Fredrickson, ED Batha, SH Bell, MG Budny, RV Levinton, FM McGuire, KM Taylor, G Zarnstorff, MC AF Chang, Z Fredrickson, ED Batha, SH Bell, MG Budny, RV Levinton, FM McGuire, KM Taylor, G Zarnstorff, MC CA TFTR Grp TI Neoclassical tearing modes in Tokamak Fusion Test Reactor experiments. I. Measurements of magnetic islands and Delta ' SO PHYSICS OF PLASMAS LA English DT Article ID TFTR; PLASMAS AB Tearing-type modes are observed in most high confinement operation regimes in the Tokamak Fusion Test Reactor (TFTR) [Nucl. Fusion 35, 1429 (1995)]. Three different methods are used to measure the magnetic island widths: external magnetic coils, internal temperature fluctuation from electron cyclotron emission (ECE) diagnostics and an experiment where the plasma major radius is rapidly shifted ("Jog" experiments), A good agreement between the three methods is observed. Numerical and analytic calculations of Delta' (the tearing instability index) are compared with an experimental measurement of Delta' using the tearing mode eigenfunction mapped from the jog data. The obtained negative Delta' indicates that the observed tearing modes cannot be explained by the classical current-gradient-driven tearing theory. (C) 1998 American Institute of Physics. C1 Princeton Univ, Plasma Phys Lab, Princeton, NJ 08543 USA. RP Chang, Z (reprint author), Princeton Univ, Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 22 TC 23 Z9 23 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1076 EP 1084 DI 10.1063/1.872627 PG 9 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600031 ER PT J AU Brizard, AJ AF Brizard, AJ TI A new Lagrangian formulation for laser-plasma interactions SO PHYSICS OF PLASMAS LA English DT Article ID LINEAR-CONVERSION; MAGNETIC-FIELD; FREE-ENERGY; PROPAGATION; CONSERVATION; ACCELERATOR; EQUATIONS; PULSES; WAVES AB A new Lagrangian structure for cold relativistic plasma electrodynamics is presented. This new formulation uses the fluid velocity v instead of the canonical-momentum Clebsch potential psi [X. L. Chen and R. N. Sudan, Phys. Fluids B 5, 1336 (1993)], As a simple application, it is used to derive (through the Noether method) new exact conservation laws associated with nonlinear laser wake-field equations in the multi-dimensional quasi-static approximation. (C) 1998 American Institute of Physics. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Brizard, AJ (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. OI Brizard, Alain/0000-0002-0192-6273 NR 26 TC 12 Z9 12 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1110 EP 1117 DI 10.1063/1.872641 PG 8 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600035 ER PT J AU Marshall, FJ Allen, MM Knauer, JP Oertel, JA Archuleta, T AF Marshall, FJ Allen, MM Knauer, JP Oertel, JA Archuleta, T TI A high-resolution x-ray microscope for laser-driven planar-foil experiments SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; NOVA AB A soft x-ray microscope (E less than or similar to 3 keV) with high spatial resolution (similar to 3 mu m) has been characterized at the University of Rochester's Laboratory for Laser Energetics and used for initial experiments oil the Omega laser system [Boehly et nl., Opt, Commun. 133, 495 (1997)] to study the hydrodynamic stability of directly driven planar foils. The microscope, which is an optimized Kirkpatrick-Baez-type design, is used to obtain four x-ray radiographs of laser-driven foils. Time-resolved images are obtained with either custom-built framing cameras (time resolution similar to 80 ps) or by using short-pulse backlighter beams (Delta t less than or similar to 200 ps). Ln the former case, a spatial resolution of similar to 7 mu m was obtained (limited by the framing camera), while in the latter case a resolution of similar to 3 mu m was obtained. This paper details the testing, calibration, and initial use of this microscope in the laboratory and on Omega. (C) 1998 American Institute of Physics. C1 Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Marshall, FJ (reprint author), Univ Rochester, Laser Energet Lab, 250 E River Rd, Rochester, NY 14623 USA. NR 21 TC 29 Z9 40 U1 1 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1118 EP 1124 DI 10.1063/1.872642 PG 7 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600036 ER PT J AU Marinak, MM Haan, SW Dittrich, TR Tipton, RE Zimmerman, GB AF Marinak, MM Haan, SW Dittrich, TR Tipton, RE Zimmerman, GB TI A comparison of three-dimensional multimode hydrodynamic instability growth on various National Ignition Facility capsule designs with HYDRA simulations SO PHYSICS OF PLASMAS LA English DT Article ID RAYLEIGH-TAYLOR INSTABILITY; INERTIAL CONFINEMENT FUSION; 3-DIMENSIONAL SIMULATIONS; DENSE-PLASMAS; TARGETS; IMPLOSION; RATES; NOVA AB Three similar cryogenic ignition capsule designs for the National Ignition Facility [J. Lindl, Phys. Plasmas 2, 3933 (1995)] are analyzed to determine surface roughness specifications required to mitigate the growth of hydrodynamic instabilities. These capsule utilize brominated plastic, polyimid and copper-doped beryllium ablator materials respectively. Direct three-dimensional numerical simulations with the HYDRA radiation hydrodynamic code [M. M. Marinak et al., Phys. Plasmas 3, 2070 (1996)] examine the growth of multimode perturbations seeded by roughness on the outer ablator and inner ice surfaces. The simulations, which showed weakly nonlinear behavior for optimized surfaces, were carried through ignition and burn. A three-dimensional multimode perturbation achieves somewhat larger amplitudes in the nonlinear regime than a corresponding two-dimensional simulation of the same rms-amplitude. The beryllium and polyimid capsules exhibit enhanced tolerance of roughness on both the ice and ablator surfaces. (C) 1998 American Institute of Physics. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Marinak, MM (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 38 TC 80 Z9 82 U1 0 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1125 EP 1132 DI 10.1063/1.872643 PG 8 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600037 ER PT J AU McKinstrie, CJ Kanaev, AV Tikhonchuk, VT Giacone, RE Vu, HX AF McKinstrie, CJ Kanaev, AV Tikhonchuk, VT Giacone, RE Vu, HX TI Three-dimensional analysis of the power transfer between crossed laser beams SO PHYSICS OF PLASMAS LA English DT Article ID ENERGY-TRANSFER AB The power transfer between crossed laser beams made possible by an ion-acoustic wave is studied. The power transfer between beams with Gaussian intensity profiles shifts the beam centroids. and alters the beam directions and focal lengths. The power transfer between beams with hot spots in their intensity profiles depends sensitively on whether the associated beam filaments intersect. (C) 1998 American Institute of Physics. C1 Univ Rochester, Dept Mech Engn, Rochester, NY 14627 USA. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP McKinstrie, CJ (reprint author), Univ Rochester, Dept Mech Engn, Rochester, NY 14627 USA. RI McKinstrie, Colin/L-7879-2013 NR 10 TC 11 Z9 11 U1 0 U2 2 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1142 EP 1147 DI 10.1063/1.872645 PG 6 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600039 ER PT J AU Carlsten, BE AF Carlsten, BE TI Emittance growth due to radial density variations of an emittance-dominated electron beam in a channel with continuous acceleration and focusing SO PHYSICS OF PLASMAS LA English DT Article AB Simulations have identified charge-density variations as driving the dominant emittance growth mechanism for high-current, low-emittance induction linacs using solenoidal focusing, once the beam enters the emittance-dominated regime. In this paper, we use the radial equation of motion, including the nonlinearities resulting from radial density variations, to understand this effect. Nonlinearities in the beam's radial motion while in a solenoid arise from the noncancellation of the effects from the diamagnetic axial magnetic field and the potential depression of the beam, if the beam density is nonuniform. Any initial density variation drives a logarithmic increase in additional higher-order density variations (through the differential betatron motion), and an emittance growth that scales logarithmically, or greater (even potentially faster than linear), with the axial distance along the accelerator. The growth rate depends on the beam current, the focusing force, and the accelerating gradient, and for typical machine parameters, the growth rate can be faster than linear with distance. The magnitude of the emittance growth depends critically on the matching of the beam from the injector to the beamline. This formalism leads to a criterion of how uniform the beam density has to be and how well the beam needs to be matched in order not to have an unacceptable emittance growth. (C) 1998 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Carlsten, BE (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. EM bcarlsten@lanl.gov NR 14 TC 6 Z9 6 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1148 EP 1161 DI 10.1063/1.872646 PG 14 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600040 ER PT J AU Tuszewski, M AF Tuszewski, M TI Particle and heat transport in a low-frequency inductively coupled plasma SO PHYSICS OF PLASMAS LA English DT Article ID DISCHARGE; DENSITY; MODEL; SIMULATION; FIELDS AB The radial profiles of induced radio frequency magnetic fields, of plasma density, and of electron temperatures are measured in low-frequency inductively coupled plasmas. Oxygen and argon data are compared to one-dimensional fluid calculations that Include time-averaged induced magnetic fields. These comparisons suggest that the induced magnetic fields broaden the profiles of input radio frequency power, somewhat flatten the density profiles, and produce an electron temperature increase in the edge region of oxygen discharges. (C) 1998 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Tuszewski, M (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 33 TC 26 Z9 26 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1198 EP 1205 DI 10.1063/1.872649 PG 8 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600044 ER PT J AU Carreras, BA Lynch, VE Diamond, PH Medvedev, M AF Carreras, BA Lynch, VE Diamond, PH Medvedev, M TI On the stiffness of the sand pile profile SO PHYSICS OF PLASMAS LA English DT Article ID SELF-ORGANIZED CRITICALITY; CONFINEMENT; DYNAMICS AB The existence of a critical gradient is an important feature of many transport models. [M. Kotschenreuther er nl., Phys, Plasmas 2, 2381 (1995)], However, fundamental differences exist in the dynamics near marginal stability, depending on whether the transport phenomena are controlled by strict (linear) marginal stability or by a self-organized criticality. One of the most striking differences is in the stiffness of the profiles, In this paper, a sand pile model is used to gain some basic understanding of the stiffness of the profile under different dynamics. (C) 1998 American Institute of Physics. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. RP Carreras, BA (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Lynch, Vickie/J-4647-2012 OI Lynch, Vickie/0000-0002-5836-7636 NR 9 TC 7 Z9 7 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 1070-664X J9 PHYS PLASMAS JI Phys. Plasmas PD APR PY 1998 VL 5 IS 4 BP 1206 EP 1208 DI 10.1063/1.872628 PG 3 WC Physics, Fluids & Plasmas SC Physics GA ZG963 UT WOS:000073057600045 ER PT J AU Soulen, RJ Fogle, WE AF Soulen, RJ Fogle, WE TI Low-temperature scales come under pressure - Reply SO PHYSICS TODAY LA English DT Letter C1 USN, Res Lab, Washington, DC 20375 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Soulen, RJ (reprint author), USN, Res Lab, Washington, DC 20375 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0031-9228 J9 PHYS TODAY JI Phys. Today PD APR PY 1998 VL 51 IS 4 BP 105 EP 105 PG 1 WC Physics, Multidisciplinary SC Physics GA ZF498 UT WOS:000072903500024 ER PT J AU Cook, AC Tissue, DT Roberts, SW Oechel, WC AF Cook, AC Tissue, DT Roberts, SW Oechel, WC TI Effects of long-term elevated [CO2] from natural CO2 springs on Nardus stricta: Photosynthesis, biochemistry, growth and phenology SO PLANT CELL AND ENVIRONMENT LA English DT Article DE Nardus stricta; Arctic; biochemistry; CO2 springs; elevated CO2; global climate change; growth; natural vegetation; Iceland; photosynthesis; phenology ID ATMOSPHERIC CARBON-DIOXIDE; ALASKAN TUSSOCK TUNDRA; ERIOPHORUM-VAGINATUM; CARBOXYLASE ACTIVITY; ACCLIMATION; ENRICHMENT; RESPONSES; SEEDLINGS; RUBISCO; PLANTS AB Plants of Nardus stricta growing near a cold, naturally emitting CO2 spring in Iceland were used to investigate the long-term (> 100 years) effects of elevated [CO2] on photosynthesis, biochemistry, growth and phenology in a northern grassland ecosystem. Comparisons were made between plants growing in an atmosphere naturally enriched with CO2 (approximate to 790 mu mol mol(-1)) near the CO2 spring and plants of the same species growing in adjacent areas exposed to ambient CO2 concentrations (approximate to 360 mu mol mol(-1)). Nardus stricta growing near the spring exhibited earlier senescence and reductions in photosynthetic capacity (approximate to 25%), Rubisco content (approximate to 26%), Rubisco activity (approximate to 40%), Rubisco activation state (approximate to 23%), chlorophyll content (approximate to 33%) and leaf area index (approximate to 22%) compared,vith plants growing away from the spring. The potential positive effects of elevated [CO2] on grassland ecosystems in Iceland are likely to be reduced by strong down-regulation in the photosynthetic apparatus of the abundant N, stricta species. C1 San Diego State Univ, Dept Biol, Global Change Res Grp, San Diego, CA 92182 USA. Texas Tech Univ, Dept Biol, Lubbock, TX 79409 USA. Data Design Grp, La Jolla, CA 92037 USA. RP Cook, AC (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Accelerator Mass Spectrometry, POB 808,L397, Livermore, CA 94551 USA. RI Oechel, Walter/F-9361-2010; Tissue, David/H-6596-2015 OI Oechel, Walter/0000-0002-3504-026X; Tissue, David/0000-0002-8497-2047 NR 52 TC 56 Z9 62 U1 0 U2 15 PU BLACKWELL SCIENCE LTD PI OXFORD PA P O BOX 88, OSNEY MEAD, OXFORD OX2 0NE, OXON, ENGLAND SN 0140-7791 J9 PLANT CELL ENVIRON JI Plant Cell Environ. PD APR PY 1998 VL 21 IS 4 BP 417 EP 425 DI 10.1046/j.1365-3040.1998.00285.x PG 9 WC Plant Sciences SC Plant Sciences GA ZW729 UT WOS:000074441900007 ER PT J AU Peiser, G Yang, SF AF Peiser, G Yang, SF TI Evidence for 1-(malonylamino) cyclopropane-1-carboxylic acid being the major conjugate of aminocyclopropane-1-carboxylic acid in tomato fruit SO PLANT PHYSIOLOGY LA English DT Article ID GLUTAMYL-TRANSFERASE PEPTIDES; 1-AMINOCYCLOPROPANE-1-CARBOXYLIC ACID; HIGHER-PLANTS; 1-(MALONYLAMINO)CYCLOPROPANE-1-CARBOXYLIC ACID; ETHYLENE BIOSYNTHESIS; IDENTIFICATION; TRANSPEPTIDASE; CONVERSION; METABOLISM; PRECURSOR AB Tomato (Lycopersicon esculentum Miller) fruit discs fed with [2,3-C-14]1-aminocyclopropane-1-carboxylic acid (ACC) formed 1-malonyl-ACC (MACC] as the major conjugate of ACC in fruit throughout all ripening stages, from immature-green through the red-ripe stage. Another conjugate of ACC, gamma-glutamyl-ACC (GACC), was formed only in mature-green fruit in an amount about 10% of that of MACC; conjugation of ACC into GACC was not detected in fruits at other ripening stages. No GACC formation was observed from etiolated mung bean (Vigna radiata [L.] Wilczek) hypocotyls, etiolated common vetch (Vicia sativum L.) epicotyls, or pea (Pisum sativum L.) root tips, etiolated epicotyls, and green stem tissue, where active conversion of ACC into MACC was observed. GACC was, however, formed in vitro in extracts from fruit of all ripening stages. GACC formation in an extract from red fruit at pH 7.15 was only about 3% of that at pH 8.0, the pH at which most assays were run. Our present in vivo data support the previous contention that MACC is the major conjugate of ACC in plant tissues, whereas GACC is a minor, ii any, conjugate of ACC. Thus, our data do not support the proposal that GACC formation could be more important than MACC formation in tomato fruit. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Vegetable Crops, Mann Lab, Livermore, CA 95616 USA. Acad Sinica, Inst Bot, Taipei, Taiwan. RP Peiser, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Vegetable Crops, Mann Lab, Livermore, CA 95616 USA. NR 22 TC 26 Z9 26 U1 1 U2 1 PU AMER SOC PLANT PHYSIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 USA SN 0032-0889 J9 PLANT PHYSIOL JI Plant Physiol. PD APR PY 1998 VL 116 IS 4 BP 1527 EP 1532 DI 10.1104/pp.116.4.1527 PG 6 WC Plant Sciences SC Plant Sciences GA ZH801 UT WOS:000073149000037 ER PT J AU Smart, LB Vojdani, F Maeshima, M Wilkins, TA AF Smart, LB Vojdani, F Maeshima, M Wilkins, TA TI Genes involved in osmoregulation during turgor-driven cell expansion of developing cotton fibers are differentially regulated SO PLANT PHYSIOLOGY LA English DT Article ID GOSSYPIUM-HIRSUTUM L; H+-ATPASE ACTIVITY; TRANSLOCATING INORGANIC PYROPHOSPHATASE; PHOSPHOENOLPYRUVATE CARBOXYLASE; VACUOLAR MEMBRANE; BETA-VULGARIS; CATALYTIC SUBUNIT; STORAGE TISSUE; EXPRESSION; PROTEIN AB Cotton (Gossypium hirsutum L.) fibers are single-celled trichomes that synchronously undergo a phase of rapid cell expansion, then a phase including secondary cell wall deposition, and finally maturation. To determine if there is coordinated regulation of gene expression during fiber expansion, we analyzed the expression of components involved in turgor regulation and a cytoskeletal protein by measuring levels of mRNA and protein accumulation and enzyme activity. Fragments of the genes for the plasma membrane proton-translocating ATPase, vacuole-ATPase, proton-translocating pyrophosphatase (PPase), phosphoenolpyruvate carboxylase, major intrinsic protein, and cu-tubulin were amplified by polymerase chain reaction and used as probes in ribonuclease protection assays of RNA from a fiber developmental series, revealing two discrete patterns of mRNA accumulation. Transcripts of all but the PPase accumulated to highest levels during the period of peak expansion (+12-15 d postanthesis [dpa]), then declined with the onset of secondary cell wall synthesis. The PPase was constitutively expressed through fiber development. Activity of the two proton-translocating-ATPases peaked at +15 dpa, whereas PPase activity peaked at +20 dpa, suggesting that all are involved in the process of cell expansion but with varying roles. Patterns of protein accumulation and enzyme activity for some of the proteins examined suggest posttranslational regulation through fiber development. C1 Lawrence Livermore Natl Lab, Dept Agron & Range Sci, Livermore, CA 95616 USA. Lawrence Livermore Natl Lab, Dept Vegetable Crops, Livermore, CA 95616 USA. Nagoya Univ, Grad Sch Bioagr Sci, Nagoya, Aichi, Japan. RP Lawrence Livermore Natl Lab, Dept Agron & Range Sci, Livermore, CA 95616 USA. EM tawilkins@ucdavis.edu RI Maeshima, Masayoshi/D-3073-2013; OI Maeshima, Masayoshi/0000-0002-1611-5481; Smart, Lawrence/0000-0002-7812-7736 NR 55 TC 106 Z9 124 U1 1 U2 9 PU AMER SOC PLANT BIOLOGISTS PI ROCKVILLE PA 15501 MONONA DRIVE, ROCKVILLE, MD 20855 USA SN 0032-0889 EI 1532-2548 J9 PLANT PHYSIOL JI Plant Physiol. PD APR PY 1998 VL 116 IS 4 BP 1539 EP 1549 DI 10.1104/pp.116.4.1539 PG 11 WC Plant Sciences SC Plant Sciences GA ZH801 UT WOS:000073149000039 PM 9536073 ER PT J AU Bonivert, WD Cushnie, G AF Bonivert, WD Cushnie, G TI New Printed Wiring Board Resource Center SO PLATING AND SURFACE FINISHING LA English DT News Item C1 Sandia Natl Labs, Livermore, CA 94551 USA. CAI Engn, Oakton, VA 22124 USA. RP Bonivert, WD (reprint author), Sandia Natl Labs, M-S 9404,Box 969, Livermore, CA 94551 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU AMER ELECTROPLATERS SOC INC PI ORLANDO PA 12644 RESEARCH PKWY, ORLANDO, FL 32826-3298 USA SN 0360-3164 J9 PLAT SURF FINISH JI Plat. Surf. Finish. PD APR PY 1998 VL 85 IS 4 BP 41 EP 42 PG 2 WC Metallurgy & Metallurgical Engineering; Materials Science, Coatings & Films SC Metallurgy & Metallurgical Engineering; Materials Science GA ZG962 UT WOS:000073057500004 ER PT J AU Albalak, RJ Capel, MS Thomas, EL AF Albalak, RJ Capel, MS Thomas, EL TI Solvent swelling of roll-cast triblock copolymer films SO POLYMER LA English DT Article DE block copolymers; roll-casting; swelling ID BLOCK POLYMER-SOLUTIONS; LAMELLAR DIBLOCK COPOLYMER; ORDERED STRUCTURE; ELECTRON-MICROSCOPY; SELECTIVE SOLVENTS; MOLECULAR-WEIGHT; MORPHOLOGY; HOMOPOLYMER AB Polystyrene-polybutadiene-polystyrene triblock copolymers were roll-cast from toluene solutions to form globally oriented films. As-processed films, containing process-related residual stresses, were exposed to solvent vapours. Three solvents were used in this study: toluene, which is a non-preferential solvent for polystyrene and polybutadiene; methyl-ethyl-ketone, which is a preferential solvent for the polystyrene blocks; and hexane, which is a preferential solvent for the polybutadiene block. Microstructural changes accompanying the solvent swelling of films with cylindrical and lamellar morphology were monitored using two-dimensional small angle X-ray scattering. Solvent swelling significantly improved the symmetry of the hexagonal packing of the cylindrical domains, which was initially distorted due to the roll-casting flow field. Solvent swelling was also found to improve the long range order in roll-cast film with lamellar morphology. Various phenomena were found to accompany the swelling and deswelling of films with both cylindrical and lamellar morphology with the three different solvents used. Especially intriguing results were observed for the case of swelling both morphologies in hexane. For films with a lamellar morphology, after 1 h of swelling and 2 h of subsequent deswelling the d-spacing decreased by 18%. For films with cylindrical morphology, a similar decrease of 9% was observed. Molecular models are presented to explain these microstructural changes, that are closely linked to the mobility of the glassy polystyrene blocks, the relaxation of process-related stress and the ability of the polybutadiene-polystyrene junctions at the interfaces to reposition and accommodate volume changes. (C) 1997 Elsevier Science Ltd. All rights reserved. C1 MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP Thomas, EL (reprint author), MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA. NR 30 TC 39 Z9 40 U1 3 U2 22 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0032-3861 J9 POLYMER JI Polymer PD APR PY 1998 VL 39 IS 8-9 BP 1647 EP 1656 DI 10.1016/S0032-3861(97)00497-7 PG 10 WC Polymer Science SC Polymer Science GA YP460 UT WOS:000071279000019 ER PT J AU Swaminarayan, S Charbon, C AF Swaminarayan, S Charbon, C TI A multiscale model for polymer crystallization. I: Growth of individual spherulites SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID GROWING 2D-SPHERULITE; MOLECULAR-WEIGHT; MORPHOLOGY; POLYPROPYLENE; POLYETHYLENE; KINETICS; CALCULUS; FIELD AB In this two-part, paper, we present a model for the solidification of semicrystalline thermoplastic polymers that links the microscopic and macroscopic length scales. The model accounts for the important physical phenomena occurring during spherulitic crystallization and predicts microstructural evolution. In this first part, we concentrate on the growth of individual spherulites. We present a fast and accurate model that predicts the shape of a spherulite as well as the path of its constitutive lamellae in any thermal situation. In part II of this paper we shall couple this new model for spherulite growth with a nucleation law and a macroscopic heat flow computation, thus enabling us to model realistic crystallization conditions. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Swaminarayan, S (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, MS G755, Los Alamos, NM 87545 USA. NR 21 TC 21 Z9 21 U1 1 U2 5 PU SOC PLASTICS ENG INC PI BROOKFIELD PA 14 FAIRFIELD DR, BROOKFIELD, CT 06804-0403 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD APR PY 1998 VL 38 IS 4 BP 634 EP 643 DI 10.1002/pen.10228 PG 10 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA ZM557 UT WOS:000073552100012 ER PT J AU Charbon, C Swaminarayan, S AF Charbon, C Swaminarayan, S TI Multiscale model for polymer crystallization. II: Solidification of a macroscopic part SO POLYMER ENGINEERING AND SCIENCE LA English DT Article ID REINFORCED THERMOPLASTIC COMPOSITES; COMPUTER-SIMULATION; SEMICRYSTALLINE POLYMERS; THERMOVISCOELASTIC MELTS; KINETICS; MORPHOLOGY; NUCLEATION AB In part I of this paper, we presented two efficient front tracking methods to simulate the growth of a spherulite within an imposed temperature field. In this second part we present a method that predicts the final microstructure in a macroscopic part by coupling these front-tracking techniques with (a) a stochastic model for the nucleation of individual spherulites, (b) a cellular model for spherulite impingement and solid fraction evolution and (c) a Finite Difference Method (FDM) for latent heat release and heat diffusion. The method tracks the physical phenomena on several length scales: a coarse grid for the heat diffusion, a fine grid for solid fraction evolution and a very fine grid for the shape of the individual spherulites and the lamellae within them. To our knowledge this is the first time that a fully coupled multiscale model has been applied to the solidification of polymers which gives realistic microstructure evolution, orientation of the different lamellae within spherulites and maps of the solid fraction and temperature fields during solidification. The model provides us with a quantitative predictive tool that can be used to optimize industrial processes. C1 Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. RP Charbon, C (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Los Alamos, NM 87545 USA. NR 30 TC 28 Z9 28 U1 2 U2 10 PU SOC PLASTICS ENG INC PI BROOKFIELD PA 14 FAIRFIELD DR, BROOKFIELD, CT 06804-0403 USA SN 0032-3888 J9 POLYM ENG SCI JI Polym. Eng. Sci. PD APR PY 1998 VL 38 IS 4 BP 644 EP 656 DI 10.1002/pen.10229 PG 13 WC Engineering, Chemical; Polymer Science SC Engineering; Polymer Science GA ZM557 UT WOS:000073552100013 ER PT J AU Raffen, R Stevens, PW Boogaard, C Schiffer, M Stevens, FJ AF Raffen, R Stevens, PW Boogaard, C Schiffer, M Stevens, FJ TI Reengineering immunoglobulin domain interactions by introduction of charged residues SO PROTEIN ENGINEERING LA English DT Article DE dimerization; electrostatics; gel filtration chromatography; immunoglobulin light chain variable domain; site-directed mutagenesis ID PERFORMANCE LIQUID-CHROMATOGRAPHY; SIZE-EXCLUSION CHROMATOGRAPHY; PROTEIN PROTEIN-INTERACTION; V-L DOMAIN; ESCHERICHIA-COLI; FV FRAGMENT; LIGHT-CHAINS; ASSOCIATION; MUTAGENESIS; SIMULATION AB The formation of the antibody variable domain binding unit (Fv) is the net result of three competing assembly reactions. The affinities of concurrent homologous interactions of heavy and light chain variable domains limits the heterologous interaction leading to productive formation of the Fv. To address the possible role of light chain dimerization in this phenomenon, the Gln38 residue at the dimer interface of an immunoglobulin light chain variable domain (V-L) was replaced by charged amino acids. The effects of these mutations on V-L homodimer formation were monitored by small-zone size exclusion HPLC and the affinities of interaction were determined by computer simulation. Reduced VL homodimerization was observed in three of the four mutants, Q38R, Q38D and Q38K, The association constants for the Q38R and Q38D homodimers were 1.2x10(4) and 3.2x10(3) M-1, respectively. This corresponded to a 20-75-fold reduction in the homodimer association constant relative to the wild-type V-L, which had an association constant of 2.4x10(5) M-1. Surprisingly, the fourth charge mutant, Q38E, had a higher association constant than the wild-type V-L. The potential for charged residues to facilitate heterodimeric assembly of immunoglobulin domains was also tested. Heterodimerization was observed between the Q38D and Q38R V(L)s, but,vith an association constant of 4,7x10(4) M-1, approximately fivefold lower than that obtained for homodimerization of the native V-L. In addition, replacement of the neutral, solvent-accessible Gln38 residue with either Asp or Arg was found to be significantly destabilizing, These results suggest that charged residues could be introduced at immunoglobulin domain interfaces to guide heterodimer formation and to minimize unfavorable competing homologous associations. Nonetheless, these apparently simple modifications may also result in unintended consequences that are likely to depend upon structural features of particular variable domains. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. Northwestern Univ, Dept Biomed Engn, Evanston, IL 60208 USA. RP Stevens, FJ (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. FU NIDDK NIH HHS [DK43757]; NIGMS NIH HHS [GM16829] NR 40 TC 22 Z9 22 U1 0 U2 0 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0269-2139 J9 PROTEIN ENG JI Protein Eng. PD APR PY 1998 VL 11 IS 4 BP 303 EP 309 DI 10.1093/protein/11.4.303 PG 7 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology GA ZV496 UT WOS:000074310400007 PM 9680192 ER PT J AU Beamer, LJ Carroll, SF Eisenberg, D AF Beamer, LJ Carroll, SF Eisenberg, D TI The BPI/LBP family of proteins: A structural analysis of conserved regions SO PROTEIN SCIENCE LA English DT Article DE bactericidal proteins; homology modeling; LPS-binding; X-ray crystallography ID PERMEABILITY-INCREASING PROTEIN; LIPOPOLYSACCHARIDE (LPS)-BINDING PROTEIN; AMINO-TERMINAL FRAGMENT; GRAM-NEGATIVE BACTERIA; BINDING-PROTEIN; ESCHERICHIA-COLI; LPS; NEUTROPHILS; NEUTRALIZATION; ACTIVATION AB Two related mammalian proteins, bactericidal/permeability-increasing protein (BPI) and lipopolysaccharide-binding protein (LBP), share high-affinity binding to lipopolysaccharide (LPS), a glycolipid found in the outer membrane of Gram-negative bacteria. The recently determined crystal structure of human BPI permits a structure/function analysis, presented here, of the conserved regions of these two proteins sequences. In the seven known sequences of BPI and LBP, 102 residues are completely conserved and may be classified in terms of location, side-chain chemistry, and interactions with other residues. We find that the mast highly conserved regions Lie at the interfaces between the tertiary structural elements that help create two apolar lipid-binding pockets. Most of the conserved polar and charged residues appear to be involved in inter-residue interactions such as II-bonding. However, in both BPI and LBP a subset of conserved residues with positive charge (lysines 42, 48, 92, 95, and 99 of BPI) have no apparent structural role. These residues cluster at the tip of the NH2-terminal domain, and several coincide with residues known to affect LPS binding; thus, it seems likely that these residues make electrostatic interactions with negatively charged groups of LPS. Overall differences in charge and electrostatic potential between BPI and LBP suggest that BPI's bactericidal activity is related to the high positive charge of its NH2-terminal domain. A model of human LBP derived from the BPI structure provides a rational basis for future experiments, such as site-directed mutagenesis and inhibitor design. C1 Univ Calif Los Angeles, DOE Lab Struct Biol, Inst Mol Biol, Los Angeles, CA 90095 USA. Xoma Corp, Berkeley, CA 94710 USA. Univ Missouri, Dept Biochem, Columbia, MO 65211 USA. RP Univ Calif Los Angeles, DOE Lab Struct Biol, Inst Mol Biol, POB 951570, Los Angeles, CA 90095 USA. EM david@mib.ucla.edu NR 34 TC 104 Z9 113 U1 1 U2 8 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0961-8368 EI 1469-896X J9 PROTEIN SCI JI Protein Sci. PD APR PY 1998 VL 7 IS 4 BP 906 EP 914 PG 9 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZG646 UT WOS:000073024800008 PM 9568897 ER PT J AU Carney, JPJ Kissel, L Pratt, RH Roy, SC Sen Gupta, SK AF Carney, JPJ Kissel, L Pratt, RH Roy, SC Sen Gupta, SK TI Elastic photon scattering from excited states of atoms and ions SO RADIATION PHYSICS AND CHEMISTRY LA English DT Article AB The elastic scattering of photons from excited state configurations of carbon atoms and ions is considered, using the S-matrix approach, for configurations involving varying numbers of K and L electrons, with any remaining electrons being placed in an outer (N) shell. Situations where the scattering cross section is much larger or smaller than that for the ground state configuration are identified. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Calif Lawrence Livermore Natl Lab, Div V L41, Livermore, CA 94551 USA. Bose Inst, Dept Phys, Calcutta 700009, W Bengal, India. N Bengal Univ, USIC, Darjeeling 734430, India. RP Carney, JPJ (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 3 TC 2 Z9 2 U1 0 U2 0 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND J9 RADIAT PHYS CHEM JI Radiat. Phys. Chem. PD APR-JUN PY 1998 VL 51 IS 4-6 BP 371 EP 372 DI 10.1016/S0969-806X(97)00142-4 PG 2 WC Chemistry, Physical; Nuclear Science & Technology; Physics, Atomic, Molecular & Chemical SC Chemistry; Nuclear Science & Technology; Physics GA ZU325 UT WOS:000074185400015 ER PT J AU Gabel, D Philipp, KHI Wheeler, FJ Huiskamp, R AF Gabel, D Philipp, KHI Wheeler, FJ Huiskamp, R TI The compound factor of the (10)B(n,alpha)(7)Li reaction from borocaptate sodium and the relative biological effectiveness of recoil protons for induction of brain damage in boron neutron capture therapy SO RADIATION RESEARCH LA English DT Article ID RAT SPINAL-CORD; CELLS; IRRADIATION; MELANOMA; HAMSTER; TUMORS; B-10(N; RBE AB To make clinical trials of boron neutron capture therapy safe for patients, it is necessary to know the relative biological effectiveness (RBE) of the radiation components and the compound factor of the boron carrier to be used. Here a method is derived to determine the RBE of recoil protons and the compound factor of compounds from in vivo experiments with different concentrations of boron. The method uses a simultaneous fit of both these parameters to all experimental data. This method is applied to the studies of tolerance of healthy tissue in dogs at the High Flux Reactor in Petten, The Netherlands. The RBE for the recoil protons generated by the neutrons present in the epithermal neutron beam [together with the RBE of the protons from the (14)N(n,p)(14)C reaction] for induction of severe neurological symptoms was found to be 3.93 +/- 0.43 (95% confidence limits 3.06-4.79), and 2.33 +/- 0.14 (2.04-2.61) for induction of changes detectable by magnetic resonance imaging. The compound factor for Na(2)B(12)H(11)SH in brain tissue, using severe neurological symptoms as end point, was determined to be 0.37 +/- 0.06 (95% confidence limits 0.24-0.50). For changes detectable by magnetic resonance imaging, the value was found to be 0.65 +/- 0.04 (0.58-0.73). (C) 1998 by Radiation Research Society. C1 Univ Bremen, Dept Chem, D-28334 Bremen, Germany. ECN Petten, NL-1755 ZG Petten, Netherlands. Idaho Natl Lab, Idaho Falls, ID 83415 USA. RP Gabel, D (reprint author), Univ Bremen, Dept Chem, POB 330440, D-28334 Bremen, Germany. NR 33 TC 16 Z9 16 U1 0 U2 1 PU RADIATION RESEARCH SOC PI LAWRENCE PA 810 E TENTH STREET, LAWRENCE, KS 66044 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD APR PY 1998 VL 149 IS 4 BP 378 EP 386 DI 10.2307/3579701 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA ZD209 UT WOS:000072662300011 PM 9525503 ER PT J AU Rademacher, SE Borak, TB Zeitlin, C Heilbronn, L Miller, J AF Rademacher, SE Borak, TB Zeitlin, C Heilbronn, L Miller, J TI Wall effects observed in tissue-equivalent proportional counters from 1.05 GeV/nucleon iron-56 particles SO RADIATION RESEARCH LA English DT Article ID HEAVY CHARGED-PARTICLES AB Tissue-equivalent proportional counters (TEPCs) have been used to measure energy deposition in simulated volumes of tissue ranging in diameter from 0.1 to 10 mu m. There has been some concern that the wall used to define the volume of interest could influence energy deposition within the sensitive volume because it has a density significantly greater than that of the cavity gas. These effects become important for high-velocity heavy ions. Measurements of energy deposition were made for 1 GeV/nucleon iron particles in a TEPC simulating a 1-mu m-diameter sphere of tissue. The TEPC was nested within a particle spectrometer that provided identification and flight path of individual particles. Energy deposition was studied as a function of pathlength through the TEPC. Approximately 30% of the energy transfer along trajectories through the center of the detector escapes the sensitive volume. The response of the TEPC, for trajectories through the detector, is always larger than calculations for energy loss in a homogeneous medium. This enhancement is greatest for trajectories near the cavity/wall interface. An integration of the response indicates that charged-particle equilibrium is essentially achieved for a wail thickness of 2.54 mm. However, estimates of the linear energy transfer for the incident particles are influenced by these wall effects. (C) 1998 by Radiation Research Society. C1 Colorado State Univ, Dept Radiol Hlth Sci, Ft Collins, CO 80523 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Borak, TB (reprint author), Colorado State Univ, Dept Radiol Hlth Sci, Ft Collins, CO 80523 USA. RI Heilbronn, Lawrence/J-6998-2013 OI Heilbronn, Lawrence/0000-0002-8226-1057 NR 26 TC 22 Z9 22 U1 0 U2 1 PU RADIATION RESEARCH SOC PI OAK BROOK PA 2021 SPRING RD, STE 600, OAK BROOK, IL 60521 USA SN 0033-7587 J9 RADIAT RES JI Radiat. Res. PD APR PY 1998 VL 149 IS 4 BP 387 EP 395 DI 10.2307/3579702 PG 9 WC Biology; Biophysics; Radiology, Nuclear Medicine & Medical Imaging SC Life Sciences & Biomedicine - Other Topics; Biophysics; Radiology, Nuclear Medicine & Medical Imaging GA ZD209 UT WOS:000072662300012 PM 9525504 ER PT J AU Fullwood, RR Hall, RE Martinez-Guridi, G Uryasev, S Sampath, SG AF Fullwood, RR Hall, RE Martinez-Guridi, G Uryasev, S Sampath, SG TI Relating aviation service difficulty reports to accident data for safety trend prediction SO RELIABILITY ENGINEERING & SYSTEM SAFETY LA English DT Article AB Commercial aviation fatalities are predicted (Fulwood et al., 'Relating aviation service difficulty reports to accident data for safety trend prediction', BNL Tech. Rpt 63018, March 1996(1)) using linear superposition of the time-dependent spectra of key aircraft systems' difficulties reporting in FAA's Service Difficulty Reports (SDR (DOT, FAA, 'Flight standards service difficulty program', Order 8010.2, Feb. 22, 1978, reissued 4:5/14/81 (2))) data base. The fitting coefficients are found by a linear regression model (referred to as 'the model') to FAA's Accident Incident Data System (AIDS (DOT/FAA, 'Aviation standards accident/incident data system-AIDS', Users Guide VS ASAS-D-335, July 1982 (3))) covering 5.5 years beginning January 1990. The model was tested by dividing the data approximately in half, using the first half to calibrate the model for prediction of the second half. A second test did the opposite. A third test used the first 60 months of data to predict the following 6 months. These tests (Fig. 5) showed good agreement between the model and ADDS data. The deficiency frequency of ATA (Aircraft Transportation Association) systems is reported (Table 2). Third-order fitting of the AIDS data was also used for prediction. All methods are compared in Fig. 4. The model was deemed superior because it reflects inspections and may be updated with SDR data from the Internet. The magnitude of the model's fining coefficients indicate systems importances to the results. (C) 1998. Published by Elsevier Science Limited. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Fed Aviat Adm, Atlantic City, NJ 08405 USA. RP Fullwood, RR (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. RI URYASEV, Stan/O-5231-2014 OI URYASEV, Stan/0000-0001-6950-3966 NR 0 TC 0 Z9 0 U1 0 U2 2 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0951-8320 J9 RELIAB ENG SYST SAFE JI Reliab. Eng. Syst. Saf. PD APR PY 1998 VL 60 IS 1 BP 83 EP 87 DI 10.1016/S0951-8320(97)00156-7 PG 5 WC Engineering, Industrial; Operations Research & Management Science SC Engineering; Operations Research & Management Science GA ZM817 UT WOS:000073579300007 ER PT J AU Mazzucato, E AF Mazzucato, E TI Numerical study of microwave reflectometry in plasmas with two-dimensional turbulent fluctuations SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID DENSITY-FLUCTUATIONS; TOKAMAK PLASMAS; TFTR; SCATTERING AB This article describes a numerical study of the role played by two-dimensional turbulent fluctuations in microwave reflectometry-a radar technique for density measurements using the reflection of electromagnetic waves from a plasma cutoff. The results indicate that, if the amplitude of fluctuations is below a threshold which is set by the spectrum of poloidal wave numbers, the measured backward field appears to originate from a virtual location behind the reflecting layer, and to arise from the phase modulation of the probing wave, with an amplitude given by one-dimensional geometric optics. These results suggest a possible scheme for turbulence measurements in tokamaks, when the backward field is collected with a wide aperture antenna, and the virtual reflecting layer is imaged onto the plane of an array of detectors. Such a scheme should be capable of providing additional information on the nature of the short-scale turbulence observed in tokamaks, which still remains one of the unresolved issues in fusion research. (C) 1998 American Institute of Physics. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Mazzucato, E (reprint author), Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 27 TC 32 Z9 32 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 1998 VL 69 IS 4 BP 1691 EP 1698 DI 10.1063/1.1148828 PG 8 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA ZJ144 UT WOS:000073183900023 ER PT J AU Bluhm, H Pan, SH Xu, L Inoue, T Ogletree, DF Salmeron, M AF Bluhm, H Pan, SH Xu, L Inoue, T Ogletree, DF Salmeron, M TI Scanning force microscope and vacuum chamber for the study of ice films: Design and first results SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article AB We present the design of a scanning force microscope and vacuum chamber for the growth and imaging of ice films in thermodynamic equilibrium and under controlled super or undersaturation. The apparatus allows measurements in the temperature range from -60 to +80 degrees C in a controlled water vapor atmosphere. First results on the morphology and the frictional properties of thin ice films on mica cleavage faces are presented. The films are found to grow in a two-dimensional manner, often exhibiting dendritic growth shapes. The lateral force measured on ice is higher than that observed on the surrounding substrate. (C) 1998 American Institute of Physics. [S0034-6748(98)05804-3]. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Salmeron, M (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. EM salmeron@stm.lbl.gov RI Ogletree, D Frank/D-9833-2016 OI Ogletree, D Frank/0000-0002-8159-0182 NR 13 TC 25 Z9 25 U1 2 U2 11 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 1998 VL 69 IS 4 BP 1781 EP 1784 DI 10.1063/1.1148841 PG 4 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA ZJ144 UT WOS:000073183900036 ER PT J AU Korzekwa, RA Grothaus, MG Hutcherson, RK Roush, RA Brown, R AF Korzekwa, RA Grothaus, MG Hutcherson, RK Roush, RA Brown, R TI Destruction of hazardous air pollutants using a fast rise time pulsed corona reactor SO REVIEW OF SCIENTIFIC INSTRUMENTS LA English DT Article ID DISCHARGE AB Increasingly stringent environmental regulation imposed on both the military and civilian sectors has created a growing demand for alternative abatement methods for a variety of hazardous compounds. One alternative, the nonthermal plasma, shows promise of providing an efficient means for the destruction of dilute concentrations of hazardous air pollutants. The Dahlgren Laboratory of the Naval Surface Warfare Center has extensively investigated one type of nonthermal plasma discharge, the pulsed corona reactor, for the destruction of volatile organic compounds and chemical warfare agents. In this reactor, a fast rise time (similar to 10 ns), short duration (<100 ns), high-voltage pulse is repetitively delivered to a wire-cylinder electrode geometry, thereby producing a multitude of streamer discharges along its length. The resulting nonthermal plasma contains highly reactive chemical radicals which can interact with and destroy the hazardous molecules entrained in the ambient atmosphere flowing through the reactor volume. Increased electrical efficiency was obtained using a combination of high efficiency constant-current capacitor-charging high repetition-rate spark gap switching, and resonant energy transfer to the reactor. Promising results have been obtained for toluene, methylene chloride, and dichlorodifluoromethane in air at concentrations of a few hundred parts per million. The device has been operated at voltages up to 30 kV, pulse repetition rates up to 1.4 kHz, and flow rates up to 60 l/min. Detailed electrical measurements have been made to properly characterize the electrical properties of the pulsed corona reactor and to validate subsequent improvements in the reactor energy efficiency. (C) 1998 American Institute of Physics. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. SW Res Inst, San Antonio, TX 78228 USA. OSRAM Sylvania Inc, Beverly, MA 01915 USA. Fed Bur Invest, Engn Res Facil, Quantico, VA 22135 USA. USN, Ctr Surface Warfare, Dahlgren, VA 22448 USA. RP Korzekwa, RA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 18 TC 25 Z9 27 U1 0 U2 8 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0034-6748 J9 REV SCI INSTRUM JI Rev. Sci. Instrum. PD APR PY 1998 VL 69 IS 4 BP 1886 EP 1892 DI 10.1063/1.1148859 PG 7 WC Instruments & Instrumentation; Physics, Applied SC Instruments & Instrumentation; Physics GA ZJ144 UT WOS:000073183900055 ER PT J AU Hawryluk, RJ AF Hawryluk, RJ TI Results from deuterium-tritium tokamak confinement experiments SO REVIEWS OF MODERN PHYSICS LA English DT Review ID FUSION-TEST-REACTOR; TOROIDAL ALFVEN EIGENMODES; REVERSED MAGNETIC SHEAR; ION-CYCLOTRON EMISSION; DIII-D TOKAMAK; D-T OPERATION; HIGH-TEMPERATURE PLASMAS; NEUTRAL BEAM INJECTION; ALPHA-PARTICLE LOSS; L-H TRANSITION AB Recent scientific and technical progress in magnetic fusion experiments has resulted in the achievement of plasma parameters (density and temperature) which made possible the production of significant bursts of fusion power from deuterium-tritium fuels and the first studies of the physics of burning plasmas. The key scientific issues in studying the reacting plasma core are plasma confinement, magnetohydrodynamic (MHD) stability, and the confinement and loss of energetic fusion products from the reacting fuel ions. Progress in the development of regimes of operation that both have good confinement and are MHD stable has made possible a broad study of problems in burning-plasma physics. The technical and scientific results from deuterium-tritium experiments on the Joint European Torus (JET) and the Tokamak Fusion Test Reactor (TFTR) are reviewed, with particular emphasis on alpha-particle physics issues. C1 Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 342 TC 61 Z9 62 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0034-6861 EI 1539-0756 J9 REV MOD PHYS JI Rev. Mod. Phys. PD APR PY 1998 VL 70 IS 2 BP 537 EP 587 DI 10.1103/RevModPhys.70.537 PG 51 WC Physics, Multidisciplinary SC Physics GA ZJ478 UT WOS:000073219700006 ER PT J AU Graham, AL Mammoli, AA Busch, MB AF Graham, AL Mammoli, AA Busch, MB TI Effects of demixing on suspension rheometry SO RHEOLOGICA ACTA LA English DT Article DE particle migration; suspension rheometry; numerical simulation-demixing ID INDUCED PARTICLE MIGRATION; CONCENTRATED SUSPENSIONS; COUETTE-FLOW; NMR; SPHERES AB It is well known that particles in initially well-mixed suspensions subjected to inhomogeneous shear flows can migrate and establish particle concentration gradients and non-Newtonian velocity profiles. In this study we introduce a modified version of the shear-induced migration model to predict transient torque reductions in torsional startup flows and transient pressure drop reductions in capillary developing flows. Special attention is devoted to the relationship between the evolution of the driving forces and various mechanisms that contribute to the shear-induced migration of the suspended particles. This analysis reveals that suspension rheometry can complement other techniques, such as nuclear magnetic resonance (NMR) imaging, in qualitatively and quantitatively evaluating the model parameters. C1 Univ Calif Los Alamos Natl Lab, ESA, EPE, Los Alamos, NM 87545 USA. Univ Western Australia, Dept Mech & Mat Engn, Nedlands, WA 6907, Australia. RP Graham, AL (reprint author), Univ Calif Los Alamos Natl Lab, ESA, EPE, MS J576, Los Alamos, NM 87545 USA. NR 28 TC 4 Z9 4 U1 0 U2 1 PU SPRINGER VERLAG PI NEW YORK PA 175 FIFTH AVE, NEW YORK, NY 10010 USA SN 0035-4511 J9 RHEOL ACTA JI Rheol. Acta PD APR PY 1998 VL 37 IS 2 BP 139 EP 150 DI 10.1007/s003970050100 PG 12 WC Mechanics SC Mechanics GA ZN144 UT WOS:000073614300006 ER PT J AU Lucklum, R Behling, C Hauptmann, P Cernosek, RW Martin, SJ AF Lucklum, R Behling, C Hauptmann, P Cernosek, RW Martin, SJ TI Error analysis of material parameter determination with quartz-crystal resonators SO SENSORS AND ACTUATORS A-PHYSICAL LA English DT Article; Proceedings Paper CT 9th International Conference on Solid-State Sensors and Actuators CY JUN 16-19, 1997 CL CHICAGO, ILLINOIS SP IEEE Electron Devices Soc DE acoustic sensors; material parameter determination AB The application of quartz-crystal resonators for materials science is based on the dependence of acoustic-wave propagation on the film shear modulus and density. In contrast to the well-known chemical-sensor applications, the shear modulus determination of a thin film needs a complete electrical impedance (or admittance) analysis and a complex fitting procedure of the measured responses. This contribution concentrates on different error sources in the procedure to deter-mine shear parameters. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Otto Von Guericke Univ, Inst Measurement Technol & Elect, IPE, D-39016 Magdeburg, Germany. Sandia Natl Labs, Microsensors Res & Dev Dept, Albuquerque, NM 87185 USA. RP Lucklum, R (reprint author), Otto Von Guericke Univ, Inst Measurement Technol & Elect, IPE, POB 4120, D-39016 Magdeburg, Germany. EM ralf@ipe.et.uni-magdeburg.de NR 15 TC 17 Z9 17 U1 0 U2 0 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0924-4247 J9 SENSOR ACTUAT A-PHYS JI Sens. Actuator A-Phys. PD APR 1 PY 1998 VL 66 IS 1-3 BP 184 EP 192 DI 10.1016/S0924-4247(98)00006-5 PG 9 WC Engineering, Electrical & Electronic; Instruments & Instrumentation SC Engineering; Instruments & Instrumentation GA ZJ338 UT WOS:000073204000030 ER PT J AU Molina, PE Ajmal, M Abumrad, NN AF Molina, PE Ajmal, M Abumrad, NN TI Energy metabolism and fuel mobilization: From the perioperative period to recovery SO SHOCK LA English DT Article ID INSULIN-INDUCED HYPOGLYCEMIA; PROTEIN-SYNTHESIS; SKELETAL-MUSCLE; INTESTINAL ADAPTATION; LEUCINE KINETICS; SURGICAL STRESS; BETA-ENDORPHIN; BODY PROTEIN; AMINO-ACIDS; GLUCOSE AB To determine the metabolic responses to surgical trauma, we assessed the rates of whole body (WB) proteolysis and glucose turnover using established isotopic techniques in combination with interorgan amino acid and substrate balances (using arteriovenous differences times flow) after laparotomy, Circulating levels of hormones and mediators known to affect these parameters were also examined. Mongrel dogs (n = 5-8 per group) were studied postoperatively under general anesthesia (immediate postoperative period) and at 3 days postoperatively (3 dPO) and 2 weeks later, Our results show that the immediate postoperative period is characterized by significant hyperglycemia, secondary to decreased glucose clearance (without any alterations in the rates of hepatic glucose production) and significant increase in gut proteolysis, with a mild increase in WB proteolysis. The gut proteolysis accounted for nearly 40% of WB proteolysis, At 3 dPO, blood glucose levels returned to normal, whereas the rate of WB proteolysis was maximally increased. Gut proteolysis was mildly elevated and accounted for nearly 8% of WB proteolysis, All metabolic parameters were back to near basal at 2 weeks postoperatively. These metabolic changes were accompanied by significant elevations in the plasma levels of endogenous morphine and cortisol and lower glucagon and insulin growth factor-1 levels in the immediate postoperative period and at 3 dPO. These studies underscore the importance of the gut as a reservoir of amino acids during the immediate postoperative period, accounting for more than one-third of WB proteolysis. At 3 dPO, when maximal stimulation of WB proteolysis and amino acid oxidation are observed, the contribution from the gut is negligible and is most likely replaced by breakdown from skeletal muscle. C1 N Shore Univ Hosp, Dept Surg, Manhasset, NY USA. RP Molina, PE (reprint author), Brookhaven Natl Lab, NSUH Surg Metab Lab, Bldg 490, Upton, NY 11973 USA. FU NIGMS NIH HHS [7RO1GM50567-05] NR 49 TC 9 Z9 9 U1 0 U2 0 PU BIOMEDICAL PRESS PI AUGUSTA PA 1021 15TH ST, BIOTECH PARK STE 9,, AUGUSTA, GA 30901 USA SN 1073-2322 J9 SHOCK JI Shock PD APR PY 1998 VL 9 IS 4 BP 241 EP 248 DI 10.1097/00024382-199804000-00002 PG 8 WC Critical Care Medicine; Hematology; Surgery; Peripheral Vascular Disease SC General & Internal Medicine; Hematology; Surgery; Cardiovascular System & Cardiology GA ZG131 UT WOS:000072968700002 PM 9565251 ER PT J AU Gray, LJ Paulino, GH AF Gray, LJ Paulino, GH TI Crack tip interpolation, revisited SO SIAM JOURNAL ON APPLIED MATHEMATICS LA English DT Article DE fracture mechanics; stress intensity factors; crack tip interpolation; hypersingular boundary integrals; eigenfunction expansion ID BOUNDARY ELEMENT METHOD; QUARTER-INFINITE CRACK; HYPERSINGULAR INTEGRALS; ISOPARAMETRIC ELEMENTS; FRACTURE-MECHANICS; SINGULAR-INTEGRALS; INTENSITY FACTORS; HALF-SPACE; STRESS; CORNERS AB It is well known that the near tip displacement field on a crack surface can be represented in a power series in the variable root r, where r is the distance to the tip. It is shown herein that the coefficients of the linear terms on the two sides of the crack are equal. Equivalently, the linear term in the crack opening displacement vanishes. The proof is a completely general argument, valid for an arbitrary (e.g., multiple, nonplanar) crack configuration and applied boundary conditions. Moreover, the argument holds for other equations, such as Laplace. A limit procedure for calculating the surface stress in the form of a hypersingular boundary integral equation is employed to enforce the boundary conditions along the crack faces. Evaluation of the finite surface stress and examination of potentially singular terms lead to the result. Inclusion of this constraint in numerical calculations should result in a more accurate approximation of the displacement and stress fields in the tip region, and thus a more accurate evaluation of stress intensity factors. C1 Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. Univ Calif Davis, Dept Civil & Environm Engn, Davis, CA 95616 USA. RP Gray, LJ (reprint author), Oak Ridge Natl Lab, Div Math & Comp Sci, Oak Ridge, TN 37831 USA. RI Paulino, Glaucio/A-2426-2008; Horvath, Agnes/B-3954-2012 NR 57 TC 43 Z9 43 U1 0 U2 1 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1399 J9 SIAM J APPL MATH JI SIAM J. Appl. Math. PD APR PY 1998 VL 58 IS 2 BP 428 EP 455 PG 28 WC Mathematics, Applied SC Mathematics GA ZC097 UT WOS:000072539600004 ER PT J AU Dawson, CN Wheeler, MF Woodward, CS AF Dawson, CN Wheeler, MF Woodward, CS TI A two-grid finite difference scheme for nonlinear parabolic equations SO SIAM JOURNAL ON NUMERICAL ANALYSIS LA English DT Article DE error estimates; finite differences; mixed finite elements; nonlinear; superconvergent ID ELEMENTS AB We present a two-level finite difference scheme for the approximation of nonlinear parabolic equations. Discrete inner products and the lowest-order Raviart-Thomas approximating space are used in the expanded mixed method in order to develop the finite difference scheme. Analysis of the scheme is given assuming an implicit time discretization. In this two-level scheme, the full nonlinear problem is solved on a "coarse" grid of size H. The nonlinearities are expanded about the coarse grid solution and an appropriate interpolation operator is used to provide values of the coarse grid solution on the fine grid in terms of superconvergent node points. The resulting linear but nonsymmetric system is solved on a "fine" grid of size h. Some a priori error estimates are derived which show that the discrete L-infinity(L-2) and L-2(H-1) errors are O(h(2) + H4-d/2 + Delta t), where d greater than or equal to 1 is the spatial dimension. C1 Univ Texas, Texas Inst Computat & Appl Math, Austin, TX 78712 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, Livermore, CA 94551 USA. RP Dawson, CN (reprint author), Univ Texas, Texas Inst Computat & Appl Math, Austin, TX 78712 USA. RI Woodward, Carol/M-4008-2014 NR 11 TC 69 Z9 73 U1 0 U2 2 PU SIAM PUBLICATIONS PI PHILADELPHIA PA 3600 UNIV CITY SCIENCE CENTER, PHILADELPHIA, PA 19104-2688 USA SN 0036-1429 J9 SIAM J NUMER ANAL JI SIAM J. Numer. Anal. PD APR PY 1998 VL 35 IS 2 BP 435 EP 452 DI 10.1137/S0036142995293493 PG 18 WC Mathematics, Applied SC Mathematics GA ZC449 UT WOS:000072580500001 ER PT J AU Nevins, MR Macal, CM Joines, JC AF Nevins, MR Macal, CM Joines, JC TI A discrete-event simulation model for seaport operations SO SIMULATION LA English DT Article DE transportation; logistics; infrastructure; planning; military; mobility; seaport; maritime; PORTSIM (TM); MODSIM (TM) ID PORT AB Discrete-event simulation has been used to assess detailed processes ata seaports. Seaport operations are labor-intensive and require extensive use of personnel and machinery. The ability to conduct seaport operations efficiently can be improved significantly through proper utilization of seaport assets. The simulation described has been written in MODSIM II and addresses seaport operations in the context of military mobility. The simulation allows for multiple cargo types as well as multiple ship types. The overall goal of the simulation has been to determine seaport throughput capability. C1 Argonne Natl Lab, Decis & Informat Sci Div, Argonne, IL 60439 USA. Transportat Engn Agcy, Mil Traff Management Command, Newport News, VA 23606 USA. RP Nevins, MR (reprint author), Argonne Natl Lab, Decis & Informat Sci Div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 13 TC 16 Z9 18 U1 0 U2 1 PU SIMULATION COUNCILS INC PI SAN DIEGO PA PO BOX 17900, SAN DIEGO, CA 92117 USA SN 0037-5497 J9 SIMULATION JI Simulation PD APR PY 1998 VL 70 IS 4 BP 213 EP 223 DI 10.1177/003754979807000401 PG 11 WC Computer Science, Interdisciplinary Applications; Computer Science, Software Engineering SC Computer Science GA 160EW UT WOS:000078218300001 ER PT J AU Hubbell, JM Sisson, JB AF Hubbell, JM Sisson, JB TI Advanced tensiometer for shallow or deep soil water potential measurements SO SOIL SCIENCE LA English DT Article DE tensiometer; soil moisture potential; advanced tensiometer ID FLUCTUATIONS AB Tensiometers are required for measuring soil-water potential at depths greater than several meters to quantify the direction and rate of soil-water movement. This paper describes a permanently installed tensiometer (advanced tensiometer) designed to measure soil-water potentials at any depth below land surface,This advanced tensiometer was designed with a removable pressure transducer to allow for field calibration and servicing and has two parts, a permanently installed outer tensiometer assembly and a removable transducer assembly. The permanently installed portion has a porous cup, an adapter containing a reservoir of water, and an outer guide pipe that extends to the land surface. The removable electronic pressure transducer assembly has a stopper on the bottom, a connector to attach the stopper to a pressure transducer, and an inner guide tube to raise and lower the assembly. The transducer assembly is lowered into the outer tensiometer assembly until the stopper connects and seals into the permanently installed adapter,This configuration of the advanced tensiometer allows it to be installed at any depth. Advanced tensiometers were operated with no maintenance at depths of 2 to 4.8 meters for periods of more than 3 months. The nearly constant temperature condition in boreholes provided stable, long-term water potential values and reduced field maintenance. C1 Lockhead Martin Idaho Technol, Idaho Natl Engn & Environm Lab, Idaho Falls, ID 83415 USA. RP Hubbell, JM (reprint author), Lockhead Martin Idaho Technol, Idaho Natl Engn & Environm Lab, POB 1625,MS 2107, Idaho Falls, ID 83415 USA. EM jmh@inel.gov; sys@inel.gov NR 29 TC 24 Z9 25 U1 0 U2 4 PU LIPPINCOTT WILLIAMS & WILKINS PI PHILADELPHIA PA 227 EAST WASHINGTON SQ, PHILADELPHIA, PA 19106 USA SN 0038-075X J9 SOIL SCI JI Soil Sci. PD APR PY 1998 VL 163 IS 4 BP 271 EP 277 DI 10.1097/00010694-199804000-00002 PG 7 WC Soil Science SC Agriculture GA ZK682 UT WOS:000073350600002 ER PT J AU Maxwell, EL AF Maxwell, EL TI METSTAT - The solar radiation model used in the production of the national solar radiation database (NSRDB) SO SOLAR ENERGY LA English DT Article ID IRRADIANCE; SURFACE AB This paper describes selected aspects of the METSTAT (Meteorological/Statistical) solar radiation model. METSTAT was developed specifically to support the production of the National Solar Radiation Data Base for the United States. The model was used to estimate hourly values of direct normal, diffuse horizontal, and global horizontal solar radiation for those times and locations for which measured data were not available. The input parameters for METSTAT include total and opaque cloud cover, aerosol optical depth, precipitable water vapor, ozone, surface albedo, snow depth, days-since-last-snowfall, atmospheric pressure and present weather. The model employs deterministic algorithms to generate acc;rate monthly means for each element for each hour and statistical algorithms to simulate the statistical and stochastic characteristics of multiyear solar radiation data sets. (C) 1998 Elsevier Science Ltd. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Maxwell, EL (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. NR 29 TC 67 Z9 77 U1 1 U2 13 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0038-092X J9 SOL ENERGY JI Sol. Energy PD APR PY 1998 VL 62 IS 4 BP 263 EP 279 DI 10.1016/S0038-092X(98)00003-6 PG 17 WC Energy & Fuels SC Energy & Fuels GA ZV524 UT WOS:000074313300002 ER PT J AU Kocha, SS Montgomery, D Peterson, MW Turner, JA AF Kocha, SS Montgomery, D Peterson, MW Turner, JA TI Photoelectrochemical decomposition of water utilizing monolithic tandem cells SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article; Proceedings Paper CT International Symposium on Solar Energy Materials CY SEP 02-06, 1996 CL CANCUN, MEXICO SP Natl Univ Mexico, Ctr Energy Res, Mexican Acad Mat Res DE decomposition; monolithic tandem cells ID SEMICONDUCTING PHOTOELECTRODES; SPLITTING WATER; EFFICIENCY; ELECTRODES; H2O2 AB Photovoltaic tandem cells consisting of a gallium indium phosphide (GaInP2) homojunction grown epitaxially upon a gallium arsenide (GaAs) homojunction, with a GaAs tunnel-diode interconnection were utilized to photoelectrochemically decompose water in a 1 M sulfuric acid electrolyte solution. Using a sol-gel process, a platinum colloid in water was used to modify the illuminated front surface of the device to catalyze the water decomposition process. A unique feature of this device is that the hydrogen and oxygen are co-evolved from the illuminated surface. The exact mechanism of the water decomposition process is not fully understood at this time. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Kocha, SS (reprint author), Natl Renewable Energy Lab, 1617 Cole Blvd, Golden, CO 80401 USA. RI Kocha, Shyam/E-4347-2010; Schaff, William/B-5839-2009 NR 20 TC 24 Z9 24 U1 2 U2 31 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD APR PY 1998 VL 52 IS 3-4 BP 389 EP 397 DI 10.1016/S0927-0248(97)00245-6 PG 9 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA ZQ253 UT WOS:000073838800017 ER PT J AU Fernandez, AM Calixto, ME Sebastian, PJ Gamboa, SA Hermann, AM Noufi, RN AF Fernandez, AM Calixto, ME Sebastian, PJ Gamboa, SA Hermann, AM Noufi, RN TI Electrodeposited and selenized (CuInSe2) (CIS) thin films for photovoltaic applications SO SOLAR ENERGY MATERIALS AND SOLAR CELLS LA English DT Article; Proceedings Paper CT International Symposium on Solar Energy Materials CY SEP 02-06, 1996 CL CANCUN, MEXICO SP Natl Univ Mexico, Ctr Energy Res, Mexican Acad Mat Res DE thin films; selenization; stoichiometry AB In the present communication, the authors report results on the characterization of electrodeposited and selenized (CuInSe2) (CIS) thin films, The selenization process was carried out using a technique called chemical vapor transport by gas (CVTG). The precursors as well as selenized films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electron microprobe analysis (EPMA). The film stoichiometry improved after selenization at 550 degrees C. The films were formed with a mixed composition of the binary as well as the ternary phases. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Nacl Autonoma Mexico, Ctr Invest Energia, Temixco 62580, Morelos, Mexico. Univ Colorado, Dept Phys, Boulder, CO 80309 USA. Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Fernandez, AM (reprint author), Univ Nacl Autonoma Mexico, Ctr Invest Energia, Temixco 62580, Morelos, Mexico. OI Calixto, Ma. Estela/0000-0002-9611-3346 NR 14 TC 16 Z9 31 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-0248 J9 SOL ENERG MAT SOL C JI Sol. Energy Mater. Sol. Cells PD APR PY 1998 VL 52 IS 3-4 BP 423 EP 431 DI 10.1016/S0927-0248(97)00240-7 PG 9 WC Energy & Fuels; Materials Science, Multidisciplinary; Physics, Applied SC Energy & Fuels; Materials Science; Physics GA ZQ253 UT WOS:000073838800020 ER PT J AU Hoogeveen, GW Riley, P AF Hoogeveen, GW Riley, P TI The search for solar gravity-mode oscillations in the solar wind using Ulysses plasma data SO SOLAR PHYSICS LA English DT Article AB A recent report that energetic particles measured in the solar wind may be influenced by solar gravity-mode (g-mode) oscillations motivated the search for g-mode signatures in the Ulysses solar wind plasma data. Ulysses solar wind plasma data from 1 March 1992 through the 12 April 1996 were examined in this study for signs of possible solar oscillations. The multi-taper method for spectral analysis was used to look for significant spectral peaks in the entire four-year data set, as well as in the smaller, more heliographically homogenous data set over the solar poles. Several frequencies satisfying certain significance requirements were found in the g-mode frequency range in both data sets that also agree with the previously published findings. However, these identifications are shown to be false detections, and hence the frequencies found cannot be identified as solar g modes. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Hoogeveen, GW (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 15 TC 14 Z9 14 U1 0 U2 0 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0038-0938 J9 SOL PHYS JI Sol. Phys. PD APR PY 1998 VL 179 IS 1 BP 167 EP 177 DI 10.1023/A:1005034632554 PG 11 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZH383 UT WOS:000073103000010 ER PT J AU Phillips, WS Rutledge, JT Fairbanks, TD Gardner, TL Miller, ME Maher, BS AF Phillips, WS Rutledge, JT Fairbanks, TD Gardner, TL Miller, ME Maher, BS TI Reservoir fracture mapping using microearthquakes: Two oilfield case studies SO SPE RESERVOIR EVALUATION & ENGINEERING LA English DT Article; Proceedings Paper CT 1996 SPE Annual Technical Conference and Exhibition CY OCT 06-09, 1996 CL DENVER, COLORADO SP Soc Petr Engineers ID CRYSTALLINE ROCK; GAS-FIELD; PLANES; TEXAS AB Patterns of microearthquakes detected downhole defined fracture orientation and extent in the Austin chalk, Giddings field, Texas, and in the 76 field, Clinton County, Kentucky. At two sites in the Austin chalk we detected more than 480 and 770 microearthquakes, respectively, during hydraulic stimulation, and more than 3,200 during primary production in Clinton County. The data were of high enough quality that 20%, 31%, and 53% of the events could be located, respectively. Reflected-wave data constrained microearthquake locations to the stimulated depths at the base of the Austin chalk. In plan view, microearthquakes defined elongate fracture zones extending from the stimulation wells parallel to the regional fracture trend. However, the widths of the stimulated zones differed by a factor of five between the two Austin chalk sites, suggesting a large difference in the population of ancillary fractures. Post-stimulation production was much higher from the wider zone. In Clinton County, microearthquakes defined low-angle, reverse-fault fracture zones above and below a producing zone. Associations with depleted production intervals indicated that the mapped fractures had been drained previously. Drilling showed that the fractures currently contain brine. The seismic behavior was consistent with stress changes associated with poroelastic effects above and below a drained volume or with the mass exchange of brine replacing produced oil. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Ryder Scott Co Petr Engineers, Houston, TX USA. Exxon Explorat Co, Houston, TX USA. NR 43 TC 4 Z9 4 U1 0 U2 2 PU SOC PETROLEUM ENG PI RICHARDSON PA 222 PALISADES CREEK DR,, RICHARDSON, TX 75080 USA SN 1094-6470 J9 SPE RESERV EVAL ENG JI SPE Reserv. Eval. Eng. PD APR PY 1998 VL 1 IS 2 BP 114 EP 121 PG 8 WC Energy & Fuels; Engineering, Petroleum; Geosciences, Multidisciplinary SC Energy & Fuels; Engineering; Geology GA ZK932 UT WOS:000073378900004 ER PT J AU Wang, Q Almond, DP Saunders, GA Palmer, SB Lim, CM Goretta, KC AF Wang, Q Almond, DP Saunders, GA Palmer, SB Lim, CM Goretta, KC TI Ultrasonic studies of flux-line pinning in superconducting Bi2Sr2CaCu2O8+y SO SUPERCONDUCTOR SCIENCE & TECHNOLOGY LA English DT Article ID HIGH-TC SUPERCONDUCTORS; HIGH-TEMPERATURE SUPERCONDUCTORS; THERMALLY ACTIVATED DISSIPATION; OXIDE SUPERCONDUCTORS; VORTEX LATTICE; MAGNETIC-FIELD; ATTENUATION; DEPENDENCE; YBA2CU3O7; STATE AB Measurements have been made of ultrasonic shear wave attenuation and sound velocity in highly textured polycrystalline samples of Bi2Sr2CaCu2O8+y in magnetic fields up to 9 T and at temperatures down to 4.2 K. Magnetic field dependent attenuation peaks and velocity enhancements were in good agreement with theoretical predictions based on the assumptions of the thermally assisted flux-flow model of the mixed state. Flux-line pinning activation energy obtained from the data showed a weak anisotropy, similar to 160 K for field parallel and similar to 240 K for field perpendicular to the c-axis. The flux-line lattice was found to be fully pinned at lowest temperatures. Experiments were also performed in low magnetic fields (up to 9 mT), but showed no evidence of reported ultrasonic effects that could be attributed to weak superconductivity in grain boundaries. C1 Univ Bath, Sch Phys & Mat Sci, Bath BA2 7AY, Avon, England. Univ Warwick, Dept Phys, Coventry CV4 7AL, W Midlands, England. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Wang, Q (reprint author), Univ Bath, Sch Phys & Mat Sci, Bath BA2 7AY, Avon, England. NR 24 TC 2 Z9 2 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-2048 J9 SUPERCOND SCI TECH JI Supercond. Sci. Technol. PD APR PY 1998 VL 11 IS 4 BP 383 EP 391 DI 10.1088/0953-2048/11/4/007 PG 9 WC Physics, Applied; Physics, Condensed Matter SC Physics GA ZH061 UT WOS:000073068200006 ER PT J AU Kovar, M Kasza, RV Griffiths, K Norton, PR Williams, GP Van Campen, D AF Kovar, M Kasza, RV Griffiths, K Norton, PR Williams, GP Van Campen, D TI Synchrotron radiation FTIR spectroscopic studies of water on Ni(110) SO SURFACE REVIEW AND LETTERS LA English DT Article ID H2O ADSORPTION; SURFACES; OXYGEN; COADSORPTION; ORIENTATION; MONOLAYER; BILAYER; CU(110); PT(111) AB The adsorption of water on Ni(110) at 92-230 K has been studied by Fourier transform infrared reflection-absorption spectroscopy (FTIR-RAS) in the 200-2000 cm(-1) frequency range using a synchrotron radiation source. For water adsorbed at 90-180 K and coverage theta (0 less than or equal to theta less than or equal to 0.5 monolayers), two IR bands at frequencies of similar to 667 and similar to 806 cm(-1) can always be observed despite the absence of an O-H stretch band. For water adsorbed at 180 K followed by annealing to 230 K, two IR, bands are again observed, at 767 and 947 cm(-1). In both cases we attribute the bands to water wagging and rocking modes. At 180 K, they are rather broad and indicative of interactions in the ordered c(2 x 2) water layer; long range dipole-dipole interactions could be important in stabilizing this 0.5 ML structure at 180 K. At 230 K the bands are believed to originate from the water molecules in water-hydroxyl complexes which occur in well-ordered 2 x 1 islands. C1 Univ Western Ontario, Interface Sci Western, London, ON N6A 5B7, Canada. Univ Western Ontario, Dept Chem, London, ON N6A 5B7, Canada. Brookhaven Natl Lab, Natl Synchrotron Light Source, Upton, NY 11973 USA. RP Norton, PR (reprint author), Univ Western Ontario, Interface Sci Western, London, ON N6A 5B7, Canada. NR 29 TC 5 Z9 5 U1 1 U2 6 PU WORLD SCIENTIFIC PUBL CO PTE LTD PI SINGAPORE PA JOURNAL DEPT PO BOX 128 FARRER ROAD, SINGAPORE 9128, SINGAPORE SN 0218-625X J9 SURF REV LETT JI Surf. Rev. Lett. PD APR PY 1998 VL 5 IS 2 BP 589 EP 598 DI 10.1142/S0218625X98000979 PG 10 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA ZU790 UT WOS:000074235200016 ER PT J AU Thevuthasan, S Herman, GS Kim, YJ Chambers, SA Peden, CHF Wang, Z Ynzunza, RX Tober, ED Morais, J Fadley, CS AF Thevuthasan, S Herman, GS Kim, YJ Chambers, SA Peden, CHF Wang, Z Ynzunza, RX Tober, ED Morais, J Fadley, CS TI The structure of formate on TiO2(110) by scanned-energy and scanned-angle photoelectron diffraction SO SURFACE SCIENCE LA English DT Article DE carboxylic acid; chemisorption; electron-solid diffraction; electron-solid interactions, scattering, diffraction; photoelectron diffraction; photoelectron spectroscopy; single crystal surfaces; soft X-ray photoelectron spectroscopy; surface structure, morphology, roughness and topography; titanium oxide; X-ray photoelectron spectroscopy ID FORMIC-ACID DECOMPOSITION; ELECTRON-DIFFRACTION; REACTION PATHS; SURFACES; SWITCHOVER; OXIDE AB We have used high- and low-energy X-ray photoelectron diffraction to determine the structure of formate adsorbed on TiO2(110). Formate binds to the surface through both oxygens to pairs of neighboring Ti4+ cations oriented along [001] to form a 2 x 1 overlayer. The O-C-O bond angle is 126+/-4 degrees. The vertical distance between formate oxygens and surface Ti cations is 2.1+/-0.1 Angstrom. These results are in good agreement with those from Hartree-Fock total energy minimization. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Thevuthasan, S (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RI Morais, Jonder/E-5022-2013; OI Morais, Jonder/0000-0002-4143-1208; Peden, Charles/0000-0001-6754-9928 NR 18 TC 53 Z9 53 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 1 PY 1998 VL 401 IS 2 BP 261 EP 268 DI 10.1016/S0039-6028(97)01092-3 PG 8 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA ZP016 UT WOS:000073707100016 ER PT J AU Chaturvedi, S Rodriguez, JA AF Chaturvedi, S Rodriguez, JA TI Interactions between Cs and noble metals (Cu, Ag, Au) on ZnO surfaces: electronic perturbations and alloy formation SO SURFACE SCIENCE LA English DT Article DE alkali metals; alloys; cesium; copper; gold; oxygen; silver; surface chemical reaction; X-ray photoelectron spectroscopy; zinc oxide ID GAS SHIFT REACTION; THERMAL-DESORPTION; METHANOL SYNTHESIS; CU/ZNO CATALYSTS; OXIDE SURFACES; ACTIVE-SITES; LI-AU; CESIUM; FILMS; ADSORPTION AB The adsorption of cesium on polycrystalline ZnO and the coadsorption of the alkali with noble metals (NM=Cu, Ag or Au) were investigated using X-ray and synchrotron-based photoelectron spectroscopies. At small coverages, Cs forms very strong adsorption bonds on polycrystalline ZnO with desorption temperatures that are higher than 700 K. The strength of the Cs-ZnO bond depends on the coverage of Cs, and for a saturated adlayer, the desorption of the alkali starts around 300 K. In the Cs/ZnO systems, there is a migration of oxygen toward the alkali-oxide interface, but the Cs does not become fully oxidized. When Cu or Au is deposited on Cs/ZnO, Cs moves from the alkali-oxide interface to the top of the noble metal overlayer. This migration substantially increases the thermal stability of Ca on the surface. In NM/ZnO surfaces, the metal overlayers exhibit valence bands that are significantly different from those of the corresponding bulk metals. These electronic perturbations do not facilitate the formation of Cs-NM alloys, and the Cs/NM/ZnO systems show a pattern of reactivity identical to that found for bulk samples: one can see the formation of Cs-Au alloys in Cs/Au/ZnO, whereas no alloying is found in Cs/Cu/ZnO and Cs/Ag/ZnO. The supported Cs-Au alloys are very reactive toward O-2. They decompose at temperatures between 400 and 500 K, with a fraction of the Cs desorbing into gas phase and the rest remaining chemisorbed on Au or ZnO. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Rodriguez, JA (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. EM rodrigez@bnl.gov NR 58 TC 17 Z9 18 U1 0 U2 9 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD APR 1 PY 1998 VL 401 IS 2 BP 282 EP 295 DI 10.1016/S0039-6028(97)01095-9 PG 14 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA ZP016 UT WOS:000073707100018 ER PT J AU Zhu, ZL Espenson, JH AF Zhu, ZL Espenson, JH TI Synthesis of 1,3,5-trioxanes: Catalytic cyclotrimerization of aldehydes SO SYNTHESIS-STUTTGART LA English DT Article DE methylrhenium trioxide (MTO); 1,3,5-trioxane; catalytic cyclotrimerization AB A series of 1,3,5-trioxanes derived from a single aldehyde, or from two aldehydes, were synthesized with methylrhenium trioxide as a catalyst. Cyclotrimerization of the aldehydes gave excellent yields under proper conditions, as did diethyl ketomalonate. A possible intermediate in the case of propionaldehyde was observed using H-1 NMR spectroscopy. Water inhibits both forward and reverse reactions. C1 Iowa State Univ, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. RP Espenson, JH (reprint author), Iowa State Univ, Ames Lab, Ames, IA 50011 USA. NR 14 TC 21 Z9 22 U1 2 U2 7 PU GEORG THIEME VERLAG PI STUTTGART PA P O BOX 30 11 20, D-70451 STUTTGART, GERMANY SN 0039-7881 J9 SYNTHESIS-STUTTGART JI Synthesis PD APR PY 1998 IS 4 BP 417 EP 422 PG 6 WC Chemistry, Organic SC Chemistry GA ZL474 UT WOS:000073436500010 ER PT J AU Parsons, T Thompson, GA Smith, RP AF Parsons, T Thompson, GA Smith, RP TI More than one way to stretch: a tectonic model for extension along the plume track of the Yellowstone hotspot and adjacent Basin and Range Province SO TECTONICS LA English DT Article ID SNAKE RIVER PLAIN; WESTERN UNITED-STATES; PLATE MOTIONS; NORTHERN NEVADA; EAST-AFRICAN; DIXIE VALLEY; LAVA FLOWS; IDAHO; MANTLE; RIFT AB The eastern Snake River Plain of southern Idaho poses a paradoxical problem because it is nearly aseismic and unfaulted although it appears to be actively extending in a SWNE direction continuously with the adjacent block-faulted Basin and Range Province. The plain represents the 100-km-wide track of the Yellowstone hotspot during the last similar to 16-17 m.y., and its crust has been heavily intruded by mafic magma, some of which has erupted to the surface as extensive basalt flows. Outside the plain's distinct topographic boundaries is a transition zone 30-100 km wide that has variable expression of normal faulting and magmatic activity as compared with the surrounding Basin and Range Province. Many models for the evolution of the Snake River Plain have as an integral component the suggestion that the crust of the plain became strong enough through basaltic intrusion to resist extensional deformation. However, both the boundaries of the plain and its transition zone lack any evidence of zones of strike slip or other accommodation that would allow the plain to remain intact while the Basin and Range Province extended around it; instead, the plain is coupled to its surroundings and extending with them. We estimate strain rates for the northern Basin and Range Province from various lines of evidence and show that these strains would far exceed the elastic limit of any rocks coupled to the Basin and Range; thus, if the plain is extending along with its surroundings, as the geologic evidence indicates, it must be doing so by a nearly aseismic process. Evidence of the process is provided by volcanic rift zones, indicators of subsurface dikes, which trend across the plain perpendicular to its axis. We suggest that variable magmatic strain accommodation, by emplacement and inflation of dikes perpendicular to the least principal stress in the elastic crust, allows the crust of the plain to extend nearly aseismically. Dike injection releases accumulated elastic strain but generates only the small earthquakes associated with dike propagation. The rate of dike emplacement required to accommodate the estimated longitudinal strain rate of the plain is roughly a composite width of 10 m every 1000 years for the geologically youngest and most active part of the plain. The locus of most rapid intrusion and strain has migrated toward Yellowstone and is now in the northeastern 100-150 km of the plain. Reduced magmatic input in the transition zone of the plain causes the transitional expression of seismicity and faulting there. C1 US Geol Survey, Menlo Park, CA 94025 USA. Idaho Natl Engn Lab, Idaho Falls, ID 83415 USA. Stanford Univ, Dept Geophys, Stanford, CA 94305 USA. RP Parsons, T (reprint author), US Geol Survey, 345 Middlefield Rd,Mail Stop 999, Menlo Park, CA 94025 USA. EM tparsons@octopus.wr.usgs.gov RI Parsons, Tom/A-3424-2008; OI Parsons, Tom/0000-0002-0582-4338 NR 78 TC 43 Z9 47 U1 0 U2 6 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0278-7407 J9 TECTONICS JI Tectonics PD APR PY 1998 VL 17 IS 2 BP 221 EP 234 DI 10.1029/98TC00463 PG 14 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA ZG245 UT WOS:000072981700006 ER PT J AU Schreckenbach, G Ziegler, T AF Schreckenbach, G Ziegler, T TI Density functional calculations of NMR chemical shifts and ESR g-tensors SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Review DE density functional theory; electron correlation; NMR chemical shifts; electron spin resonance; relativistic effects; transition metal complexes ID INCLUDING ATOMIC ORBITALS; AB-INITIO ECP/DFT; PERTURBATION-THEORY APPROACH; RESONANCE SHIELDING TENSORS; INHOMOGENEOUS ELECTRON-GAS; SPIN COUPLING-CONSTANTS; X-ALPHA-CALCULATIONS; UHF METHOD; MAGNETIC-SUSCEPTIBILITIES; RELATIVISTIC CALCULATIONS AB An overview is given on recent advances of density functional theory (DFT) as applied to the calculation of nuclear magnetic resonance (NMR) chemical shifts and electron spin resonance (ESR) g-tensors. This isa new research area that has seen tremendous progress and success recently; we try to present some of these developments. DFT accounts for correlation effects efficiently. Therefore, it is the only first-principle method that can handle NMR calculations on large systems like transition-metal complexes. Relativistic effects become important for heavier element compounds; here we show how they can be accounted for. The ESR g-tensor is related conceptually to the NMR shielding, and results of g-tensor calculations are presented. DFT has been very successful in its application to magnetic properties, for metal complexes in particular. However, there are still certain shortcomings and limitations, e.g., in the exchange-correlation functional, that are discussed as well. C1 Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calgary, Dept Chem, Calgary, AB T2N 1N4, Canada. RP Schreckenbach, G (reprint author), Los Alamos Natl Lab, Div Theoret, MS B268, Los Alamos, NM 87545 USA. NR 136 TC 172 Z9 175 U1 1 U2 27 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1432-881X J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD APR PY 1998 VL 99 IS 2 BP 71 EP 82 DI 10.1007/s002140050306 PG 12 WC Chemistry, Physical SC Chemistry GA ZL817 UT WOS:000073474500001 ER PT J AU Borowski, P Jordan, KD Nichols, J Nachtigall, P AF Borowski, P Jordan, KD Nichols, J Nachtigall, P TI Investigation of a hybrid TCSCF-DFT procedure SO THEORETICAL CHEMISTRY ACCOUNTS LA English DT Article DE density functional theory; two-configurational self-consistent field ID 2ND-ORDER PERTURBATION-THEORY; MOLECULAR-ORBITAL METHODS; BASIS SETS; BORON; CH2 AB In this work a family of hybrid TCSCF-DFT procedures for treating inherently two-configurational species is introduced and applied to the low-lying singlet and tripler states of B-2 and C2H4. The hybrid procedures permit self-consistent determination of the orbitals in both the TCSCF and Kohn-Sham subspaces. C1 Pacific NW Natl Lab, Environm Mol Sci Lab, High Performance Computat Chem Grp, Richland, WA 99352 USA. Univ Pittsburgh, Dept Chem, Pittsburgh, PA 15260 USA. Acad Sci Czech Republic, J Heyrovsky Inst Phys Chem, CZ-18223 Prague 8, Czech Republic. RP Nichols, J (reprint author), Pacific NW Natl Lab, Environm Mol Sci Lab, High Performance Computat Chem Grp, Richland, WA 99352 USA. RI Nachtigall, Petr/A-5691-2008; Nachtigall, Petr/A-6220-2013; OI Nachtigall, Petr/0000-0002-1628-7275; Nichols, Jeffrey/0000-0001-5454-9726 NR 26 TC 21 Z9 21 U1 0 U2 1 PU SPRINGER PI NEW YORK PA 233 SPRING ST, NEW YORK, NY 10013 USA SN 1432-881X EI 1432-2234 J9 THEOR CHEM ACC JI Theor. Chem. Acc. PD APR PY 1998 VL 99 IS 2 BP 135 EP 140 DI 10.1007/s002140050315 PG 6 WC Chemistry, Physical SC Chemistry GA ZL817 UT WOS:000073474500010 ER PT J AU Stewart, FM Antia, R Levin, BR Lipsitch, M Mittler, JE AF Stewart, FM Antia, R Levin, BR Lipsitch, M Mittler, JE TI The population genetics of antibiotic resistance II: Analytic theory for sustained populations of bacteria in a community of hosts SO THEORETICAL POPULATION BIOLOGY LA English DT Article ID ANTIMICROBIAL RESISTANCE; DRUG-RESISTANCE; ESCHERICHIA-COLI; PLASMID; EVOLUTION; ORGANISMS AB The phenomenon of antibiotic resistance is of practical importance and theoretical interest. As a foundation for further studies by simulation, experiment, and observation, we here develop a mathematical model for the dynamics of resistance among the bacteria resident in a population of hosts. The model incorporates the effects of natural selection within untreated hosts, colonization by bacteria from the environment, and the rapid increase of resistance in hosts who receive antibiotics. We derive explicit formulas for the distribution of resistance among hosts and for the rise or fall of resistance when the frequency of treatment is changed. (C) 1998 Academic Press. C1 Brown Univ, Dept Math, Providence, RI 02912 USA. Emory Univ, Dept Biol, Atlanta, GA 30322 USA. Univ Calif Los Alamos Natl Lab, Theoret Biol & Biophys Grp, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Ctr Nonlinear Studies, Los Alamos, NM 87545 USA. RP Stewart, FM (reprint author), Brown Univ, Dept Math, Box 1917, Providence, RI 02912 USA. NR 32 TC 35 Z9 35 U1 1 U2 3 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0040-5809 J9 THEOR POPUL BIOL JI Theor. Popul. Biol. PD APR PY 1998 VL 53 IS 2 BP 152 EP 165 DI 10.1006/tpbi.1997.1352 PG 14 WC Ecology; Evolutionary Biology; Genetics & Heredity SC Environmental Sciences & Ecology; Evolutionary Biology; Genetics & Heredity GA ZP388 UT WOS:000073747300006 PM 9615474 ER PT J AU Selwyn, GS Weiss, CA Sequeda, F Huang, C AF Selwyn, GS Weiss, CA Sequeda, F Huang, C TI In-situ analysis of particle contamination in magnetron sputtering processes SO THIN SOLID FILMS LA English DT Article; Proceedings Paper CT 5th European Vacuum Conference (EVC 5) / 10th International Conference on Thin Films (ICTF 10) CY SEP 23-27, 1996 CL UNIV SALAMANCA, SALAMANCA, SPAIN SP Spanish Vacuum Soc, Int Union Vacuum Sci Technol & Applicat, Vacuum Sci & Thin Film Div HO UNIV SALAMANCA DE magnetron sputtering processes; particulate contamination; thin film products ID PARTICULATE CONTAMINATION; LIGHT-SCATTERING; GLOW-DISCHARGES; DUST PARTICLES; PLASMA; TRANSPORT AB Defects caused by particulate contamination are an important concern in the fabrication of thin film products. Often, magnetron sputtering processes are used for this purpose. Particle contamination can cause electrical shorting, pin holes, problems with photolithography, adhesion failure, as well as visual and cosmetic defects. Particle contamination generated during thin film processing can be detected using laser light scattering, a powerful diagnostic technique that provides real-time, in situ imaging of particles > 0.3 mu m in diameter. Using this technique, the causes, sources and influences on particles in plasma and non-plasma processes may be independently evaluated and corrected. Several studies employing laser light scattering have demonstrated both homogeneous and heterogeneous causes of particle contamination. In this paper, we demonstrate that the mechanisms for particle generation, transport and trapping during magnetron sputter deposition are different from the mechanisms reported in previously studied plasma etch processes. During magnetron sputter deposition, one source of particle contamination is linked to portions of the sputtering target surface exposed to weaker plasma density. In this region, film redeposition is followed by filament or nodule growth and enhanced trapping that increases filament growth. Eventually, the filaments effectively 'short-circuit' the sheath, causing high currents to flow through these features. This, in turn, causes heating failure of the filament fracturing and ejecting the filaments into the plasma and onto the substrate. Evidence of this effect has been observed in semiconductor (IC) fabrication and storage disk manufacturing. Discovery of this mechanism in both technologies suggests that this mechanism may be universal to many sputtering processes. (C) 1998 Elsevier Science S.A. C1 Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Mat Res, Sputtering Syst Div, N Congers, NY 10920 USA. Seagate Peripherals Disk Div, Milpitas, CA 95035 USA. RP Selwyn, GS (reprint author), Univ Calif Los Alamos Natl Lab, Div Phys, M-S E526, Los Alamos, NM 87545 USA. EM gss@lanl.gov NR 21 TC 7 Z9 7 U1 0 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0040-6090 J9 THIN SOLID FILMS JI Thin Solid Films PD APR 1 PY 1998 VL 317 IS 1-2 BP 85 EP 92 DI 10.1016/S0040-6090(97)00603-2 PG 8 WC Materials Science, Multidisciplinary; Materials Science, Coatings & Films; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZX454 UT WOS:000074517700021 ER PT J AU Lenhard, RJ Oostrom, M AF Lenhard, RJ Oostrom, M TI A parametric model for predicting relative permeability-saturation-capillary pressure relationships of oil-water systems in porous media with mixed wettability SO TRANSPORT IN POROUS MEDIA LA English DT Article DE multiphase flow; hysteresis; mixed wettability; constitutive relations; mixed-wet capillary pressure model ID GOVERNING MULTIPHASE FLOW; PORE-LEVEL; FLUID-FLOW; RESERVOIRS AB A parametric two-phase, oil-water relative permeability/capillary pressure model for petroleum engineering and environmental applications is developed for porous media in which the smaller pores are strongly water-wet and the larger pores tend to be intermediate- or oil-wet. A saturation index, which can vary from 0 to 1, is used to distinguish those pores that are strongly water-wet from those that have intermediate- or oil-wet characteristics. The capillary pressure submodel is capable of describing main-drainage and hysteretic saturation-path saturations for positive and negative oil-water capillary pressures. At high oil-water capillary pressures, an asymptote is approached as the water saturation approaches the residual water saturation. At low oil-water capillary pressures (i.e. negative), another asymptote is approached as the oil saturation approaches the residual oil saturation. Hysteresis in capillary pressure relations, including water entrapment, is modeled. Relative permeabilities are predicted using parameters that describe main-drainage capillary pressure relations and accounting for how water and oil are distributed throughout the pore spaces of a porous medium with mixed wettability. The capillary pressure submodel is tested against published experimental data, and an example of how to use the relative permeability/capillary pressure model for a hypothetical saturation-path scenario involving several imbibition and drainage paths is given. Features of the model are also explained. Results suggest that the proposed model is capable of predicting relative permeability/capillary pressure characteristics of porous media mixed wettability. C1 Pacific NW Lab, Environm Technol Div, Richland, WA 99352 USA. Sultan Qaboos Univ, Dept Soil & Water Sci, Al Khoud 123, Oman. RP Lenhard, RJ (reprint author), Pacific NW Lab, Environm Technol Div, MS K9-33, Richland, WA 99352 USA. NR 19 TC 27 Z9 27 U1 0 U2 4 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0169-3913 J9 TRANSPORT POROUS MED JI Transp. Porous Media PD APR PY 1998 VL 31 IS 1 BP 109 EP 131 DI 10.1023/A:1006503406056 PG 23 WC Engineering, Chemical SC Engineering GA ZW077 UT WOS:000074371600006 ER PT J AU Gaasterland, T AF Gaasterland, T TI Structural genomics taking shape SO TRENDS IN GENETICS LA English DT Editorial Material C1 Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. RP Gaasterland, T (reprint author), Argonne Natl Lab, Div Math & Comp Sci, 9700 S Cass Ave,MCS 221,Room D227, Argonne, IL 60439 USA. NR 7 TC 22 Z9 24 U1 0 U2 1 PU ELSEVIER SCI LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND SN 0168-9525 J9 TRENDS GENET JI Trends Genet. PD APR PY 1998 VL 14 IS 4 BP 135 EP 135 DI 10.1016/S0168-9525(98)01430-9 PG 1 WC Genetics & Heredity SC Genetics & Heredity GA ZG656 UT WOS:000073025900004 PM 9594659 ER PT J AU Ho, CK Webb, SW AF Ho, CK Webb, SW TI Capillary barrier performance in heterogeneous porous media SO WATER RESOURCES RESEARCH LA English DT Article ID STOCHASTIC-ANALYSIS; UNSATURATED FLOW; SOILS AB The effects of heterogeneities on the performance of capillary barriers is investigated by numerically simulating three systems comprised of a fine soil layer overlying a coarse gravel layer with (1) homogeneous, (2) layered heterogeneous, and (3) random heterogeneous property fields. The amount of lateral diversion above the coarse layer under steady state infiltration conditions is compared among the simulations. Results indicate that the performance of capillary barriers can be significantly influenced by the spatial variability of hydraulic properties. In the layered heterogeneous systems, realizations with highly stratified regions within the fine layer performed best and resulted in localized capillary barriers that delayed breakthrough into the coarse layer. In contrast, realizations of the random heterogeneous system performed worst because of channeled flow that produced numerous localized regions of breakthrough into the coarse layer. Results of the homogeneous model were comparable to the mean results of the layered heterogeneous realizations, but homogeneous results underpredicted the frequency and amount of breakthrough for all realizations of the random heterogeneous system. These results indicate that homogeneous models can be used to estimate the average behavior of layered heterogeneous systems with reasonable accuracy. In addition, engineered capillary barriers may be improved through emplacement and packing methods that induce highly stratified features within the fine layer of a capillary barrier system. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Ho, CK (reprint author), Sandia Natl Labs, POB 5800,MS 1324, Albuquerque, NM 87185 USA. NR 22 TC 25 Z9 25 U1 0 U2 4 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD APR PY 1998 VL 34 IS 4 BP 603 EP 609 DI 10.1029/98WR00217 PG 7 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA ZE657 UT WOS:000072816600006 ER PT J AU Maxwell, RM Pelmulder, SD Tompson, AFB Kastenberg, WE AF Maxwell, RM Pelmulder, SD Tompson, AFB Kastenberg, WE TI On the development of a new methodology for groundwater-driven health risk assessment SO WATER RESOURCES RESEARCH LA English DT Article ID HYDROGEOLOGICAL DECISION-ANALYSIS; VOLATILE ORGANIC-COMPOUNDS; WASTE MANAGEMENT SITES; DRINKING-WATER; POROUS-MEDIA; MACROSCOPIC DISPERSION; STOCHASTIC-ANALYSIS; ENGINEERING DESIGN; REGULATORY POLICY; SOLUTE TRANSPORT AB A methodology and hypothetical case study are presented for incorporation of uncertainty and variability into calculations of human health risk appropriate for regional, or basin-scale, groundwater management problems. Uncertainty in well water concentration is introduced through complex contaminant migration patterns in the subsurface. Variability is considered in parameters related to individual behavior patterns and biological effects and to groundwater extraction and distribution networks. A joint uncertainty and variability (JUV) analysis is used to generate a two-dimensional distribution or risk surface that spans both transport uncertainty as well as individual variability. Cuts in this distributional surface (fractiles of variability and percentiles of uncertainty) are presented and discussed. Comparisons with alternative approaches based upon deterministic transport models are also made. In addition, important distinctions are made between the case where household water is derived from the nearest well and the case where household water is mixed from many wells in a distribution system. C1 Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Nucl Engn, Berkeley, CA 94720 USA. Univ Calif Berkeley, Ctr Nucl & Tox Waste Management, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Geosci & Environm Technol Div, Livermore, CA 94551 USA. RP Maxwell, RM (reprint author), Univ Calif Berkeley, Dept Civil & Environm Engn, Berkeley, CA 94720 USA. EM kastenbe@nuc.berkeley.edu RI Maxwell, Reed/D-7980-2013 OI Maxwell, Reed/0000-0002-1364-4441 NR 35 TC 55 Z9 55 U1 2 U2 7 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 0043-1397 J9 WATER RESOUR RES JI Water Resour. Res. PD APR PY 1998 VL 34 IS 4 BP 833 EP 847 DI 10.1029/97WR03605 PG 15 WC Environmental Sciences; Limnology; Water Resources SC Environmental Sciences & Ecology; Marine & Freshwater Biology; Water Resources GA ZE657 UT WOS:000072816600024 ER PT J AU Clements, BE Johnson, JN Addessio, FL AF Clements, BE Johnson, JN Addessio, FL TI Wave propagation in laminates: A study of the nonhomogenized dynamic method of cells SO WAVE MOTION LA English DT Article ID COMPOSITE-MATERIALS AB The nonhomogenized dynamic method of cells (NHDMOC) method uses a truncated expansion for the particle displacement field: the expansion parameter is the local cell position vector. We derive and numerically solve the NHDMOC equations for the first-, second-, and third-order expansions, appropriate for modeling a plate-impact experiment. All materials are linear elastic. The performance of the NHDMOC is tested at each order for its ability to resolve the shock wave front as it propagates through a homogeneous target. The same performance is again tested fora shock propagating through a bilaminate target. We gives only a qualitative description of the propagating stress wave; the second-order theory performs much better; and the third-order theory gives small refinements over the second-order theory. In the third-order theory the stress is nearly always continuous across material boundaries, whereas in first-order, one commonly encounters substantial stress discontinuities. The first-order theory requires a considerable finer computational grid to achieve the same satisfactory representation of the wave profile as the third-order theory. Thus very little computational time is saved by using it. The numerical (unphysical) oscillations inherent in these calculations are largely reduced in the third-order theory, again indicating the rapid convergence of the displacement series. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Clements, BE (reprint author), Univ Calif Los Alamos Natl Lab, Grp T-1,MS B221, Los Alamos, NM 87545 USA. NR 9 TC 9 Z9 9 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0165-2125 J9 WAVE MOTION JI Wave Motion PD APR PY 1998 VL 27 IS 3 BP 193 EP 209 DI 10.1016/S0165-2125(97)00051-6 PG 17 WC Acoustics; Mechanics; Physics, Multidisciplinary SC Acoustics; Mechanics; Physics GA ZC707 UT WOS:000072608500001 ER PT J AU Basic, I Brnicevic, N Beck, U Simon, A McCarley, RE AF Basic, I Brnicevic, N Beck, U Simon, A McCarley, RE TI Compounds with cluster cations together with cluster anions [(M6X12)(EtOH)(6)](2+) besides [(Mo6Cl8)Cl4X2](2-) (M=Nb, Ta, X=Cl, Br) - Synthesis and crystal structures SO ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE LA English DT Article DE hexanuclear metal halide cluster; cluster cation-cluster anion salts; H-bridges; crystal structure ID = NB; NIOBIUM; TANTALUM; CHEMISTRY; CL; COMPLEXES; CHLORIDES; TERNARY; HALIDES; UNITS AB Compounds consisting of both cluster cations and cluster anions of the composition [(M6X12)(EtOH)(6)][(Mo6Cl8)Cl4X2]. nEtOH . mEt(2)O (M = Nb, Ta; X = Cl, Br) have been prepared by the reaction of (M6X12)X-2 . 6EtOH with (Mo6Cl8)Cl-4. IR data are given for three compounds. The structures of [(Nb6Cl12)(EtOH)(6)][(Mo6Cl8)Cl-6]. 3EtOH . 3Et(2)O 1 and [(Ta6Cl12)(EtOH)(6)][(Mo6Cl8)Cl-6]. 6EtOH 2 have been solved in the triclinic space group P (1) over bar (No.2). Crystal data: 1, a = 10.641(2) Angstrom, b = 13.947(2) Angstrom, c = 15.460(3) Angstrom, alpha = 65.71(2)degrees, beta = 73.61(2)degrees, gamma = 85.11(2)degrees, V = 2005.1(8) Angstrom(3) and Z = 1; 2, a = 11.218(2) Angstrom b = 12.723(3) Angstrom, c = 14.134(3) Angstrom, alpha = 108.06(2)degrees, beta = 101.13(2)degrees, gamma = 91.18(2)degrees, V = 1874.8(7) Angstrom(3) and Z = 1. Both structures are built of octahedral [(M6Cl12)(EtOH)6](2+) cluster cations and [(Mo6Cl8)Cl-6](2-) cluster anions, forming distorted CsCl structure types. The Nb-Nb and Ta-Ta bond lengths of 2.904 Angstrom and 2.872 Angstrom (mean values), respectively, are rather short, indicating weak M-O bonds. All O atoms of coordinated EtOH molecules are involved in H bridges. The Mo-Mo distances of 2.603 Angstrom and 2.609 Angstrom (on average) are characteristic for the [(Mo6Cl8)Cb](2-) anion, but there is a clear correlation between the number of hydrogen bridges to the terminal Cl and the corresponding Mo-Cl distances. C1 Rudjer Boskovic Inst, Zagreb 10001, Croatia. Max Planck Inst Festkorperforsch, D-70569 Stuttgart, Germany. Iowa State Univ, Dept Chem, Ames, IA 50011 USA. US DOE, Ames Lab, Ames, IA 50011 USA. RP Brnicevic, N (reprint author), Rudjer Boskovic Inst, POB 1016, Zagreb 10001, Croatia. NR 23 TC 24 Z9 24 U1 0 U2 2 PU WILEY-V C H VERLAG GMBH PI WEINHEIM PA BOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANY SN 0044-2313 J9 Z ANORG ALLG CHEM JI Z. Anorg. Allg. Chem. PD APR PY 1998 VL 624 IS 4 BP 725 EP 732 DI 10.1002/(SICI)1521-3749(199804)624:4<725::AID-ZAAC725>3.0.CO;2-X PG 8 WC Chemistry, Inorganic & Nuclear SC Chemistry GA ZG685 UT WOS:000073029100031 ER PT J AU McCarthy, JF Czerwinski, KR Sanford, WE Jardine, PM Marsh, JD AF McCarthy, JF Czerwinski, KR Sanford, WE Jardine, PM Marsh, JD TI Mobilization of transuranic radionuclides from disposal trenches by natural organic matter SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article DE contaminant transport; natural organic matter; humic substances; fulvic acid; transuranic; actinides; radionuclides; groundwater; complexation; waste disposal ID LASER FLUORESCENCE SPECTROSCOPY; HUMIC SUBSTANCES; METAL-IONS; MOLECULAR-WEIGHT; SANDY AQUIFER; FULVIC-ACIDS; ADSORPTION; COMPLEXATION; AMERICIUM(III); MECHANISMS AB Transuranic (TRU) radionuclides in groundwater at the Oak Ridge National Laboratory migrate rapidly and with little retardation of the radionuclides over distances of 80 m. Several interacting hydrogeochemical processes contribute to the observed releases of actinides (Cm-244 and Am-241) from the shallow unlined disposal trenches, through the highly weathered, fractured shale (saprolite) and to the surface-water seeps at White Oak Creek. Major releases are promoted when seasonal fluctuations in the water table permit groundwater to contact actinide-contaminated waste. Local recharge of stormwater into the trenches appears to permit minor releases, perhaps due to transient saturation within the trenches but above the local water table. Although the hydrogeology of the site permits contact of the TRU waste with the groundwater, the expected inorganic species of the actinides should strongly adsorb to the layer silicates and mineral oxides of the shale saprolite, Yet the timing of the actinide releases relative to when rising groundwater intercepts the trenches suggests that actinide transport is rapid, and the relative magnitude of peak actinide levels in wells near the trenches and at downgradient seeps suggests that then is very limited retention of the actinides by the formation. Based on anion exchange chromatography of the groundwater and geochemical modeling, the mobilization and transport of the actinides is demonstrated to result from complexation of the actinides by natural organic matter (NOM). Storm events contribute to mobilization by promoting hydrologic links between the TRU waste and groundwater, and by increasing the concentration of NOM in the mobile soil and groundwater. This study demonstrates that even in formations characterized by abundant mineral phases known to strongly adsorb actinides, the actinides can be transported essentially conservatively as NOM complexes. (C) 1998 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. MIT, Dept Nucl Engn, Cambridge, MA 02139 USA. Colorado State Univ, Dept Earth Resources, Ft Collins, CO 80523 USA. RP McCarthy, JF (reprint author), Oak Ridge Natl Lab, Div Environm Sci, POB 2008, Oak Ridge, TN 37831 USA. RI Sanford, William/F-7380-2016 OI Sanford, William/0000-0001-9085-1367 NR 66 TC 93 Z9 94 U1 3 U2 23 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD MAR 31 PY 1998 VL 30 IS 1-2 BP 49 EP 77 DI 10.1016/S0169-7722(97)00032-6 PG 29 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZG857 UT WOS:000073047000003 ER PT J AU Stafford, P Toran, L McKay, L AF Stafford, P Toran, L McKay, L TI Influence of fracture truncation on dispersion: A dual permeability model SO JOURNAL OF CONTAMINANT HYDROLOGY LA English DT Article ID GROUNDWATER-FLOW; MASS-TRANSPORT; POROUS-MEDIA; CONTAMINANT TRANSPORT; TRACER EXPERIMENTS; FIELD EXPERIMENTS; SOLUTE TRANSPORT; FISSURED ROCKS; CLAYEY TILL; NETWORKS AB Simulations with a dual permeability model show that a few discrete fractures can have a major influence on plume geometry. A limited number of truncated fractures (1-4) within a permeable matrix can create nearly circular plumes, with about the same degree of spreading in the direction transverse to the average hydraulic gradient as in the longitudinal direction. By comparison, continuous fractures in the direction of flow tend to produce elongated plumes, similar to those typically seen in granular materials. Both types of plumes have been observed in tracer experiments in fractured porous media on the Oak Ridge Reservation. Understanding the influence of fracture geometry is important in planning field characterization and subsequent remediation in fractured porous media. (C) 1998 Elsevier Science B.V. C1 Oak Ridge Natl Lab, Div Environm Sci, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Geol Sci, Knoxville, TN 37996 USA. RP Toran, L (reprint author), Temple Univ, Dept Geol, Philadelphia, PA 19022 USA. NR 48 TC 9 Z9 9 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0169-7722 J9 J CONTAM HYDROL JI J. Contam. Hydrol. PD MAR 31 PY 1998 VL 30 IS 1-2 BP 79 EP 100 DI 10.1016/S0169-7722(97)00037-5 PG 22 WC Environmental Sciences; Geosciences, Multidisciplinary; Water Resources SC Environmental Sciences & Ecology; Geology; Water Resources GA ZG857 UT WOS:000073047000004 ER PT J AU Yang, XG Shi, JX Johnson, S Swanson, B AF Yang, XG Shi, JX Johnson, S Swanson, B TI Growth of ultrathin covalently attached polymer films: Uniform thin films for chemical microsensors SO LANGMUIR LA English DT Letter ID MONOLAYERS; SURFACES AB A novel approach to covalently attached polymer films by surface functionalization and hydrosilylation reaction with reactive polymers on the surface is reported. Stable, uniform, and highly sensitive thin film sensors can thus be fabricated. The covalent attachment of polymer through a silane linker results in films with high uniformity, stability, and reasonable reproducibility as far as film thickness is concerned. Incorporation of molecular recognition reagents into the sensing film increases the sensor sensitivity dramatically, which is critical for detecting vapors such as certain explosives at parts per thousand or parts per billion levels. The sensors fabricated can detect o-nitrotoluene, a TNT simulant, at parts per billion concentrations. C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. RP Yang, XG (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 21 TC 29 Z9 36 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 31 PY 1998 VL 14 IS 7 BP 1505 EP 1507 DI 10.1021/la980001t PG 3 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZF614 UT WOS:000072914700001 ER PT J AU Trevor, JL Lykke, KR Pellin, MJ Hanley, L AF Trevor, JL Lykke, KR Pellin, MJ Hanley, L TI Two-laser mass spectrometry of thiolate, disulfide, and sulfide self-assembled monolayers SO LANGMUIR LA English DT Article ID SULFUR BOND-CLEAVAGE; ALKANETHIOL MONOLAYERS; SURFACE-ANALYSIS; THERMAL-DESORPTION; ORGANIC MONOLAYERS; GOLD SURFACES; IONIZATION; AU(111); RECOGNITION; STABILITY AB Self-assembled monolayers (SAMs) of thiolates, disulfides (RSSR+), and sulfides were studied on Au by N-2 laser desorption followed by vacuum ultraviolet (VUV) (118-nm) photoionization of secondary neutrals in a time-of-flight mass spectrometer. Dimers (RSSR+) dominated the photoionization mass spectrum from all chain lengths of alkanethiolates and disulfides studied. Nonmethyl-terminated alkanethiolates with X = (OH and COOH) were detected as dimers without loss of the terminal group. Phenyl-SAMs with X = (H, OH, OCH3, Cl, and NO2) were detected as both monomers and dimers. Thiocholesterol SAMs were detected solely as monomers. The data suggest that dimerization occurs as a result of the recombination of surface thiolates during desorption. The alkane sulfides were detected intact, but with additional monomer and dimer species present in the spectra. The appearance of dimers is not a strong function of adsorbate structure or ordering and therefore cannot be taken as evidence for or against the recently proposed model of thiolate dimers on Au surfaces. Two receptor adsorbates, resorcin[4]arene tetrasulfide and beta-cyclodextrin sulfide were examined by two-laser mass spectrometry (L2MS), but only the former gave identifiable high mass peaks. Mixed thiolate and disulfide monolayers generated both pure and mixed dimers, providing information on nearest neighbor interactions. The mixed disulfide results indicate there is a common adsorption state for thiolates and disulfides. The laser desorption and VUV photoionization cross sections for these various organosulfur SAMs were found to be similar. L2MS with VUV photoionization was nonselective in its detection of these organosulfur species and produced mass spectra with little fragmentation. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. RP Hanley, L (reprint author), Univ Illinois, Dept Chem, Chicago, IL 60607 USA. EM LHanley@uic.edu RI Pellin, Michael/B-5897-2008 OI Pellin, Michael/0000-0002-8149-9768 NR 51 TC 75 Z9 75 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 31 PY 1998 VL 14 IS 7 BP 1664 EP 1673 DI 10.1021/la971136m PG 10 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZF614 UT WOS:000072914700026 ER PT J AU Ontko, AC Angelici, RJ AF Ontko, AC Angelici, RJ TI Effects of alkyl chain length on the adsorption of n-alkyl isocyanides (R-N C) on gold powder SO LANGMUIR LA English DT Article ID SELF-ASSEMBLED MONOLAYERS; STRUCTURAL CHARACTERIZATION; ALKANETHIOLATE MONOLAYERS; ORGANOSULFUR COMPOUNDS; MOLECULAR FILMS; SURFACES; COADSORPTION; SPECTROSCOPY; DIFFRACTION; MICROSCOPY AB The chemisorption of the alkyl isocyanides n-butyl (C4H9NC), n-hexyl (C6H13NC), n-octyl (C8K17NC), n-dodecyl (C12H25NC), and n-octadecyl isocyanide (C18H37NC) On Au powder from 1,2-dichloroethane (DCE) was examined using both solution (FTIR) and surface (diffuse reflectance infrared fourier transform or DRIFT) spectroscopic techniques. For the isocyanides with fewer than 12 carbon units in their alkyl tails, equilibrium binding constants (K-1), surface coverages (n(1s) and n(a) mol/g(Au)) and qualitative rates of solution-surface equilibria in DCE solvent are the same. Competition studies between C-13-labeled C18H37NC and nonlabeled C4H9NC show that the ratio of adsorbed isocyanides at equilibrium, (C18H37NC)-C-13/C4H9NC, is 4.1. Adsorption studies show that isocyanides are bound strongly to the surface at low coverages (less than 70% of saturation coverage), but binding affinity is significantly lower at higher coverages. Studies of C18H37NC and C4H9NC in n-decane, DCE, and nitromethane (MeNO2) solvents show that solvent polarity affects the rate of monolayer formation, surface coverage, and equilibrium binding constants. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Angelici, RJ (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 43 TC 51 Z9 51 U1 0 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 31 PY 1998 VL 14 IS 7 BP 1684 EP 1691 DI 10.1021/la970807d PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZF614 UT WOS:000072914700029 ER PT J AU Subramanian, R Schneibel, JH AF Subramanian, R Schneibel, JH TI FeAl-TiC and FeAl-WC composites - melt infiltration processing, microstructure and mechanical properties SO MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING LA English DT Article; Proceedings Paper CT Symposium on Advances in Synthesis and Processing of Metal and Ceramic Matrix Composites CY FEB 09-13, 1997 CL ORLANDO, FLORIDA SP ASM Mat Synthesis & Proc Comm, ASM TMS Composite Mat Comm DE melt infiltration process; cements; carbide composites ID TITANIUM CARBIDE; CERAMIC COMPOSITES; MATRIX COMPOSITES; ROOM-TEMPERATURE; BINDER PHASE; C SYSTEM; ALUMINUM; FRACTURE; KINETICS; ALLOYS AB TiC-based and WC-based cermets were processed with iron aluminide, an intermetallic, as a binder by pressureless melt infiltration to near full density (> 97% TD). Phase equilibria calculations in the quaternary Fe-Al-Ti-C and Fe-AI-W-C systems at 1450 degrees C were performed to determine the solubility of the carbide phases in liquid iron aluminide. This was done by using Thermocalc(TM) and the results show that molten Fe-40 at.% Al in equilibrium with Ti0.512C0.488 and graphite, dissolves 4.9 at.% carbon and 63 at, ppm titanium. In the Fe-Al-W-C system, liquid Fe-40 at.% Al in equilibrium with graphite dissolves approximate to 5 at.% carbon and 1 at.% tungsten. Due to the low values for the solubility of the carbide phases in liquid iron aluminide, liquid phase sintering of mixed powders does not yield a dense, homogenous microstructure for carbide volume fractions greater than 0.70. Melt infiltration of molten FeAl into TiC and WC preforms serves as a successful approach to process cermets with carbide contents ranging from 70 to 90 vol.%, to greater than 97% TD. Also, the microstructures of cermets prepared by melt infiltration were very homogenous. Typical properties such as hardness, bend strength and fracture toughness are reported. SEM observations of fracture surfaces suggest the improved fracture toughness to result from the ductility of the intermetallic phase. Preliminary experiments for the evaluation of the oxidation resistance of iron aluminide bonded cermets indicate that they are more resistant than WC-Co cermets. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Subramanian, R (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, POB 2008, Oak Ridge, TN 37831 USA. NR 49 TC 57 Z9 62 U1 0 U2 16 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0921-5093 J9 MAT SCI ENG A-STRUCT JI Mater. Sci. Eng. A-Struct. Mater. Prop. Microstruct. Process. PD MAR 31 PY 1998 VL 244 IS 1 BP 103 EP 112 DI 10.1016/S0921-5093(97)00833-2 PG 10 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA ZH404 UT WOS:000073105400015 ER PT J AU Liu, YS Hart, PJ Schlunegger, MP Eisenberg, D AF Liu, YS Hart, PJ Schlunegger, MP Eisenberg, D TI The crystal structure of a 3D domain-swapped dimer of RNase A at a 2.1-angstrom resolution SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article DE protein structure; x-ray crystallography; protein-protein interactions; amyloid ID SEMINAL RIBONUCLEASE; PROTEIN STRUCTURES; MECHANISM; BINDING AB The dimer of bovine pancreatic ribonuclease A (RNase A) discovered by Crestfield, Stein, and Moore in 1962 has been crystallized and its structure determined and refined to a 2.1-Angstrom resolution, The dimer is 3D domain-swapped, The N-terminal helix (residues 1-15) of each subunit is swapped into the major domain (residues 23-124) of the other subunit, The dimer of bull seminal ribonuclease (BS-RNase) is also known to be domain-swapped, but the relationship of the subunits within the two dimers is strikingly different, In the RNase A dimer, the 3-stranded beta sheets of the two subunits are hydrogen-bonded at their edges to Form a continuous 6-stranded sheet across the dimer interface; in the BS-RNase dimer, it is instead the two helices that abut, Whereas the BS-RNase dimer has 2-fold molecular symmetry, the two subunits of the RNase A dimer are related by a rotation of similar to 160 degrees. Taken together, these structures show that intersubunit adhesion comes mainly from the swapped helical domain binding to the other subunit in the "closed interface" but that the overall architecture of the domain-swapped oligomer depends on the interactions in the second type of interface, the "open interface." The RNase A dimer crystals take up the dye Congo Red, but the structure of a Congo Red-stained crystal reveals no bound dye molecule. Dimer formation is inhibited by excess amounts of the swapped helical domain, The possible implications for amyloid formation are discussed. C1 Univ Calif Los Angeles, Dept Chem, DOE Lab Struct Biol & Mol Med, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Biochem, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Dept Biol Chem, Los Angeles, CA 90095 USA. Merck Sharp & Dohme Chibret AG, CH-8152 Glattbrugg, Switzerland. RP Eisenberg, D (reprint author), Univ Calif Los Angeles, Dept Chem, DOE Lab Struct Biol & Mol Med, Box 951570, Los Angeles, CA 90095 USA. EM david@pauling.mbi.ucla.edu NR 42 TC 152 Z9 155 U1 0 U2 7 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAR 31 PY 1998 VL 95 IS 7 BP 3437 EP 3442 DI 10.1073/pnas.95.7.3437 PG 6 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZE957 UT WOS:000072848500024 PM 9520384 ER PT J AU Bai, GR Tsu, IF Wang, A Foster, CM Murray, CE Dravid, VP AF Bai, GR Tsu, IF Wang, A Foster, CM Murray, CE Dravid, VP TI In situ growth of highly oriented Pb(Zr0.5Ti0.5)O-3 thin films by low-temperature metal-organic chemical vapor deposition SO APPLIED PHYSICS LETTERS LA English DT Article AB Highly oriented, polycrystalline Pb(Zr0.5Ti0.5)O-3 (PZT) thin films were successfully grown on RuO2/SiO2/(001)Si using metal-organic chemical vapor deposition (MOCVD) at 525 degrees C. The orientation of the PZT film was controlled by using MOCVD-deposited highly textured RuO2 bottom electrodes. A (001)-oriented PZT film was observed for growth on (101)-textured RuO2. In contrast, for (110) RuO2, the growth of (001) PZT was greatly suppressed while the growth of both (110) and (111) were enhanced, resulting in a poorly (001)-textured polycrystalline film. The as-grown PZT films exhibited a dense columnar microstructure with an average grain size of 150-750 nm. Both PZT films showed excellent ferroelectric properties without any postgrowth annealing, The (001) highly oriented PZT films showed significantly higher values of remnant polarization (P-r=49.7 mu C/cm(2)) and saturation polarization (P-s=82.5 mu C/cm(2)). In comparison, for the PZT films grown on (110) RuO2, P-r and P-s were 21.5 and 35.4 mu C/cm(2), respectively. (C) 1998 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Northwestern Univ, Dept Mat Sci & Engn, Evanston, IL 60208 USA. RP Bai, GR (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Dravid, Vinayak/B-6688-2009 NR 15 TC 33 Z9 33 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 30 PY 1998 VL 72 IS 13 BP 1572 EP 1574 DI 10.1063/1.121118 PG 3 WC Physics, Applied SC Physics GA ZE124 UT WOS:000072760100017 ER PT J AU Curioni, A Andreoni, W Treusch, R Himpsel, FJ Haskal, E Seidler, P Heske, C Kakar, S van Buuren, T Terminello, LJ AF Curioni, A Andreoni, W Treusch, R Himpsel, FJ Haskal, E Seidler, P Heske, C Kakar, S van Buuren, T Terminello, LJ TI Atom-resolved electronic spectra for Alq(3) from theory and experiment SO APPLIED PHYSICS LETTERS LA English DT Article ID LIGHT-EMITTING DEVICES; ELECTROLUMINESCENT AB The electronic structure of Alq(3) is investigated using density functional theory-based calculations, photoemission and near-edge x-ray absorption fine structure. The distinct features of the observed spectra are understood in terms of contributions from the different atoms and molecular orbitals. Fingerprints of the molecular bonding and of the individual atoms are identified. These results are meant to be a reference for the monitoring of chemical processes that Alq(3) may undergo during fabrication or degradation of light-emitting devices, and for the understanding of the effects of ligand or metal substitution. (C) 1998 American Institute of Physics. C1 IBM Corp, Div Res, Zurich Res Lab, CH-8803 Ruschlikon, Switzerland. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Curioni, A (reprint author), IBM Corp, Div Res, Zurich Res Lab, CH-8803 Ruschlikon, Switzerland. EM cur@zurich.ibm.com RI Treusch, Rolf/C-3935-2015 NR 14 TC 158 Z9 159 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 30 PY 1998 VL 72 IS 13 BP 1575 EP 1577 DI 10.1063/1.121119 PG 3 WC Physics, Applied SC Physics GA ZE124 UT WOS:000072760100018 ER PT J AU Liu, XY Xu, W Foiles, SM Adams, JB AF Liu, XY Xu, W Foiles, SM Adams, JB TI Atomistic studies of segregation and diffusion in Al-Cu grain boundaries SO APPLIED PHYSICS LETTERS LA English DT Article ID INTERATOMIC POTENTIALS; ALUMINUM FILMS; ELECTROMIGRATION AB The segregation of Cu atoms at Al [110] Sigma 11 and [001] Sigma 5 tilt grain boundaries was studied. Cu atoms were found to segregate to asymmetric sites at the Sigma 11 boundary and form zig-zag planar aggregates at the interface, Segregation is dominated by atomic size and local hydrostatic stress. Cu atoms prefer to occupy the prime diffusion path sires at both grain boundaries. Cu segregation raises the vacancy formation and diffusion activation energies at Sigma 11 grain boundaries, thus slowing the rate of atomic diffusion. (C) 1998 American Institute of Physics. C1 Univ Illinois, Dept Mat Sci & Engn, Urbana, IL 61801 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Livermore, CA 94550 USA. Arizona State Univ, Dept Chem Bio & Mat, Tempe, AZ 85287 USA. RP Liu, XY (reprint author), Univ Illinois, Dept Mat Sci & Engn, 1304 W Green St, Urbana, IL 61801 USA. OI Foiles, Stephen/0000-0002-1907-454X NR 11 TC 47 Z9 49 U1 1 U2 16 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 30 PY 1998 VL 72 IS 13 BP 1578 EP 1580 DI 10.1063/1.121120 PG 3 WC Physics, Applied SC Physics GA ZE124 UT WOS:000072760100019 ER PT J AU Westerberg, KW McClelland, MA Finlayson, BA AF Westerberg, KW McClelland, MA Finlayson, BA TI Finite element analysis of flow, heat transfer, and free interfaces in an electron-beam vaporization system for metals SO INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS LA English DT Article DE liquid flow; energy transport; electron-beam ID ZONE CRYSTAL-GROWTH; FREE-SURFACE; WELD POOLS; FLUID-FLOW; CONVECTION AB A numerical analysis is made of the liquid flow and energy transport in a system to evaporate metals. The energy from an electron-beam heats an axisymmetric metal disk supported by a water-cooled platform. Metal evaporates from the surface of a hot pool of liquid which is surrounded by a shell of its own solid. Flow in the pool is strongly driven by temperature-induced buoyancy and capillary forces, and is located in the transition region between laminar and turbulent flow. The evaporation rate is strongly influenced by the locations of the free boundaries. A modified finite element method is used to calculate the steady state flow and temperature fields coupled with the interface locations. The mesh is structured with spines that stretch and pivot as the interfaces move. The discretized equations are arranged in an 'arrow' matrix and are solved using the Newton-Raphson method. The electron-beam power and platform contact resistance are varied for cases involving the evaporation of aluminum. The results reveal the interaction of liquid flow, heat transfer and free interfaces. (C) 1998 John Wiley & Sons, Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Washington, Dept Chem Engn, Seattle, WA 98195 USA. RP McClelland, MA (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-460, Livermore, CA 94550 USA. NR 32 TC 12 Z9 13 U1 1 U2 6 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0271-2091 J9 INT J NUMER METH FL JI Int. J. Numer. Methods Fluids PD MAR 30 PY 1998 VL 26 IS 6 BP 637 EP 655 DI 10.1002/(SICI)1097-0363(19980330)26:6<637::AID-FLD667>3.0.CO;2-M PG 19 WC Computer Science, Interdisciplinary Applications; Mathematics, Interdisciplinary Applications; Mechanics; Physics, Fluids & Plasmas SC Computer Science; Mathematics; Mechanics; Physics GA ZB333 UT WOS:000072460500002 ER PT J AU Zheng, YJ Ornstein, RL AF Zheng, YJ Ornstein, RL TI Theoretical study of a nucleophilic addition reaction in the gas phase and in aqueous solution: peptide bond hydrolysis SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE nucleophilic addition; ab initio molecular orbital theory; SCRF; free energy barrier; enzyme catalysis ID FREE-ENERGY CHANGE; AB-INITIO; CARBONYL ADDITION; DISPLACEMENT-REACTIONS; DIELECTRIC CONTINUUM; SCF CALCULATIONS; REACTION PATHS; REACTION FIELD; MONTE-CARLO; SOLVENT AB Nucleophilic addition of hydroxide anion to N,N-dimethyl acetamide in the gas phase and in solution was elucidated using a combination of ab initio molecular orbital theory and self-consistent reaction field model. The gas phase reaction is exothermic, with a tetrahedral adduct being the product. An ion-dipole complex formed between hydroxide and N,N-dimethyl acetamide, of comparable stability to the tetrahedral adduct, was located on the potential energy surface. There is a considerable potential energy barrier separating the ion-dipole complex and the tetrahedral adduct in the gas phase. However, in aqueous solution, the ion-dipole complex disappears as a minimum. The calculated free energy barriers in solution at the HF/6-31++G** level of theory are 27.7 and 7.4 kcal mol(-1) for the forward and reverse reactions respectively; the corresponding experimental values, according to Guthrie's analysis, are 24.6 and 5.8 kcal mol(-1). In view of the previous difficulties in reproducing experimental foe energy barriers in solution for nucleophilic addition of hydroxide to formaldehyde, the present study has clearly demonstrated the potential of the ab initio self-consistent reaction field approach to study chemical reactions in solution. The effects of geometry relaxation on calculated free energy barriers have also been evaluated. (C) 1998 Elsevier Science B.V. C1 Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Univ Calif Santa Barbara, Dept Chem, Santa Barbara, CA 93106 USA. EM zheng@bioorganic.ucsb.edu NR 62 TC 12 Z9 12 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD MAR 30 PY 1998 VL 429 BP 41 EP 48 DI 10.1016/S0166-1280(97)00298-4 PG 8 WC Chemistry, Physical SC Chemistry GA ZJ046 UT WOS:000073174100005 ER PT J AU Paulsen, MD Hay, BP AF Paulsen, MD Hay, BP TI Conformational analysis of crown ethers. Part 3. Alkali and alkaline earth cation complexes of 15-crown-5 SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE molecular mechanics; MM3; crown ether; metal complex; conformation ID MOLECULAR MECHANICS MM3; CRYSTAL-STRUCTURES; FORCE-FIELD; METAL-IONS; INCLUSION-COMPOUNDS; SELECTIVE LIGANDS; RATIONAL DESIGN; IR-SPECTRUM; 12-CROWN-4; ELECTRIDES AB An extensive conformational search of 15-crown-5 complexes with the alkali and alkaline earth cations was performed with an extended MM3 force field. A detailed comparison of the search results with crystallographic data establishes that the model accurately predicts the structural features of these compounds. An improved method is reported for scanning a macrocycle conformer cavity to determine the preferred metal ion size. We demonstrate that the variations in ligand strain for different conformers as a function of metal size rationalize the crystallographically observed variations in 15-crown-5 conformation as a function of metal ion size and charge. (C) 1998 Elsevier Science B.V. C1 Pacific NW Lab, MSIN K183, Richland, WA 99352 USA. RP Pacific NW Lab, MSIN K183, POB 999, Richland, WA 99352 USA. NR 77 TC 21 Z9 21 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD MAR 30 PY 1998 VL 429 BP 49 EP 59 DI 10.1016/S0166-1280(97)00336-9 PG 11 WC Chemistry, Physical SC Chemistry GA ZJ046 UT WOS:000073174100006 ER PT J AU Csaki, C Murayama, H AF Csaki, C Murayama, H TI Discrete anomaly matching SO NUCLEAR PHYSICS B LA English DT Article ID DYNAMICAL SUPERSYMMETRY BREAKING; ELECTRIC-MAGNETIC DUALITY; ABELIAN GAUGE-THEORIES; YANG-MILLS THEORY; EXACT SUPERPOTENTIALS; ANTISYMMETRIC TENSOR; SYMMETRY; SU(N); EXAMPLES; SP(N-C) AB We extend the well-known 't Hooft anomaly matching conditions for continuous global symmetries to discrete groups. We state explicitly the matching conditions for all possible anomalies which involve discrete symmetries. There are two types of discrete anomalies, For Type I anomalies, the matching conditions always have to be satisfied regardless of the details of the massive bound state spectrum. The Type II anomalies have to be also matched except if there are fractionally charged massive bound states in the theory. We check discrete anomaly matching in recent solutions of certain N = 1 supersymmetric gauge theories, most of which satisfy these constraints, The excluded examples include the chirally symmetric phase of N = 1 pure supersymmetric Yang-Mills theories described by the Veneziano-Yankielowicz Lagrangian and certain non-supersymmetric confining theories, The conjectured self-dual theories based on exceptional gauge groups do not satisfy discrete anomaly matching nor mapping of operators, and are viable only if the discrete symmetry in the electric theory appears as an accidental symmetry in the magnetic theory and vice versa. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Csaki, C (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. EM csaki@thwk5.lbl.gov; murayama@thsrv.lbl.gov RI Murayama, Hitoshi/A-4286-2011 NR 60 TC 41 Z9 41 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 30 PY 1998 VL 515 IS 1-2 BP 114 EP 162 DI 10.1016/S0550-3213(97)00839-0 PG 49 WC Physics, Particles & Fields SC Physics GA ZF827 UT WOS:000072937200006 ER PT J AU Riotto, A AF Riotto, A TI Inflation and the nature of supersymmetry breaking SO NUCLEAR PHYSICS B LA English DT Article DE inflation; supersymmetry breaking ID COSMOLOGICAL MODULI PROBLEM; DARK-MATTER; SUPERGRAVITY THEORIES; ENTROPY CRISIS; EARLY UNIVERSE; PHYSICS; SCALE; TECHNICOLOR; MODELS; MASS AB The scale at which supersymmetry is broken and the mechanism by which supersymmetry breaking is fed down to the observable sector has rich implications on the way Nature may have chosen to accomplish inflation. We discuss a simple model for slow rollover inflation which is minimal in the sense that the inflaton may be identified with the field responsible for the generation of the mu-term. Inflation takes place at very late times and is characterized by a very low reheating temperature. This property is crucial to solve the gravitino problem and may help to ameliorate the cosmological moduli problem. The COBE normalized value of the vacuum energy driving inflation is naturally of the order of 10(11) GeV. This favors the N = 1 supergravity scenario where supersymmetry breaking is mediated by gravitational interactions. Nonetheless, smaller values of the vacuum energy are not excluded by present data on the temperature anisotropy and the inflationary scenario may be implemented in the context of new recent ideas about gauge mediation where the standard model gauge interactions can serve as the messengers of supersymmetry breaking. In this class of models supersymmetry breaking masses are usually proportional to the F-term of a gauge singlet superfield. The same F-term may provide the vacuum energy density necessary to drive inflation. The spectrum of density perturbations is characterized by a spectral index which is significantly displaced from one. The measurements of the temperature anisotropies in the cosmic microwave background radiation at the accuracy expected to result from the planned missions will be able to confirm or disprove this prediction and to help in getting some deeper insight into the nature of supersymmetry breaking. (C) 1998 Elsevier Science B.V. C1 Fermi Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Riotto, A (reprint author), Fermi Natl Accelerator Lab, NASA Fermilab Astrophys Ctr, POB 500, Batavia, IL 60510 USA. EM riotto@fnas01.fnal.gov NR 56 TC 7 Z9 7 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 30 PY 1998 VL 515 IS 1-2 BP 413 EP 435 DI 10.1016/S0550-3213(98)00039-X PG 23 WC Physics, Particles & Fields SC Physics GA ZF827 UT WOS:000072937200019 ER PT J AU Johnson, CW Bertsch, GF Dean, DJ AF Johnson, CW Bertsch, GF Dean, DJ TI Orderly spectra from random interactions SO PHYSICAL REVIEW LETTERS LA English DT Article AB We investigate the low-lying spectra of many-body systems with random two-body interactions, specifying that the ensemble be invariant under particle-hole conjugation. Surprisingly we find patterns reminiscent of more orderly interactions, such as a predominance of J = 0 ground states separated by a gap from the excited states, and evidence of phonon vibrations in the low-lying spectra. C1 Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. Univ Washington, Dept Phys, Seattle, WA 98195 USA. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RP Johnson, CW (reprint author), Louisiana State Univ, Dept Phys & Astron, Baton Rouge, LA 70803 USA. OI Dean, David/0000-0002-5688-703X NR 10 TC 162 Z9 163 U1 1 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2749 EP 2753 DI 10.1103/PhysRevLett.80.2749 PG 5 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000001 ER PT J AU Brandenburg, G Briere, RA Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, F Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB McLean, KW Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, R Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lattery, M Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Savinov, V Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Blinov, S Duboscq, JE Fisher, KD Fujino, D Fulton, R Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Wood, M Bishai, M Fast, J Gerndt, E Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Gibbons, L Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Schaffner, SF Ugolini, D Wang, R Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Frasconi, F Gao, M Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartelt, J Csorna, SE Jain, V Marka, S Freyberger, A Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Asner, DM Bliss, DW Brewer, WS Masek, G Paar, HP Sharma, TK Gronberg, J Hill, TS Kutschke, R Lange, DJ Menary, S Morrison, RJ Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Cho, K Ford, WT Park, H Rankin, P Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Coffman, DM Crowcroft, DS Dickson, M Drell, PS Ecklund, KM Ehrlich, R Elia, R Foland, AD Gaidarev, P Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Katayama, N Kim, PC Kreinick, DL Lee, T Liu, Y Ludwig, GS Masui, J Mevissen, J Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J AF Brandenburg, G Briere, RA Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, F Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB McLean, KW Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, R Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lattery, M Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Savinov, V Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Blinov, S Duboscq, JE Fisher, KD Fujino, D Fulton, R Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Wood, M Bishai, M Fast, J Gerndt, E Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M Gibbons, L Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Schaffner, SF Ugolini, D Wang, R Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Frasconi, F Gao, M Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartelt, J Csorna, SE Jain, V Marka, S Freyberger, A Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Asner, DM Bliss, DW Brewer, WS Masek, G Paar, HP Sharma, TK Gronberg, J Hill, TS Kutschke, R Lange, DJ Menary, S Morrison, RJ Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Cho, K Ford, WT Park, H Rankin, P Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Coffman, DM Crowcroft, DS Dickson, M Drell, PS Ecklund, KM Ehrlich, R Elia, R Foland, AD Gaidarev, P Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Katayama, N Kim, PC Kreinick, DL Lee, T Liu, Y Ludwig, GS Masui, J Mevissen, J Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J CA CLEO Collaboration TI New measurement of B -> D*pi branching fractions SO PHYSICAL REVIEW LETTERS LA English DT Article ID CP VIOLATION; DECAYS AB The decays Y(4S) --> , followed by B --> D*pi and D* --> D pi, permit reconstruction of all kinematic quantities that describe the sequence without reconstruction of the D, with reasonably low backgrounds. Using an integrated e(+)e(-) luminosity of 3.1 fb(-1) accumulated at the Y(4S) by the CLEO-II Il detector, we report measurements of B((B) over bar(0) --> D*(+)pi(-)) = (2.81 +/- 0.11 +/- 0.21 +/- 0.05) x 10(-3) and B(B- --> D*(0) pi(-)) = (4.34 +/- 0.33 +/- 0.34 +/- 0.18) x 10(-3). C1 Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Champaign, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Colorado, Boulder, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. BINP, RU-630090 Novosibirsk, Russia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Univ Texas, Austin, TX 78712 USA. RP Brandenburg, G (reprint author), Harvard Univ, Cambridge, MA 02138 USA. RI Schaffner, Stephen/D-1189-2011; Briere, Roy/N-7819-2014; Frasconi, Franco/K-1068-2016; OI Briere, Roy/0000-0001-5229-1039; Frasconi, Franco/0000-0003-4204-6587; Bean, Alice/0000-0001-5967-8674 NR 20 TC 19 Z9 19 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2762 EP 2766 DI 10.1103/PhysRevLett.80.2762 PG 5 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000004 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Nakano, I Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marringer, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH OHmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RC Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Nakano, I Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marringer, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH OHmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RC Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Zanetti, A Zetti, F Zucchelli, S TI Measurement of the top quark mass SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON VERTEX DETECTOR; (P)OVER-BAR-P COLLISIONS; COLLIDER DETECTOR; TEV; FERMILAB; EVENTS AB We present a measurement of the top quark mass using a sample of decays into an electron or a muon, a neutrino, and four jets. The data were collected in collisions at root s = 1.8 TeV with the Collider Detector at Fermilab and correspond to an integrated luminosity of 109 gb(-1). We measure the top quark mass to be 175.9 +/- 4.8(stat) +/- 4.9(syst) GeV/c(2). C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Johns Hopkins Univ, Baltimore, MD 21218 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Univ Illinois, Urbana, IL 61801 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Harvard Univ, Cambridge, MA 02138 USA. Univ Geneva, CH-1211 Geneva 4, Switzerland. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Florida, Gainesville, FL 32611 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Duke Univ, Durham, NC 27708 USA. Univ Chicago, Chicago, IL 60637 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Brandeis Univ, Waltham, MA 02254 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; Tartarelli, Giuseppe Francesco/A-5629-2016; OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Tartarelli, Giuseppe Francesco/0000-0002-4244-502X; Latino, Giuseppe/0000-0002-4098-3502; Wyss, Jeffery/0000-0002-8277-4012; Lancaster, Mark/0000-0002-8872-7292; Bertolucci, Sergio/0000-0003-1738-4736; Bigongiari, Ciro/0000-0003-3293-8522; Gallinaro, Michele/0000-0003-1261-2277; Turini, Nicola/0000-0002-9395-5230 NR 25 TC 88 Z9 88 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2767 EP 2772 DI 10.1103/PhysRevLett.80.2767 PG 6 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000005 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Freeman, J Friedman, J Frisch, H Fukui, Y Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giusti, G Glenzinski, D Gold, M Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kondo, K Kongeter, A Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Levis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spiegel, L Spinella, F Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zanetti, A Zetti, F Zuchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Freeman, J Friedman, J Frisch, H Fukui, Y Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giusti, G Glenzinski, D Gold, M Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Hao, W Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kondo, K Kongeter, A Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Levis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spiegel, L Spinella, F Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zanetti, A Zetti, F Zuchelli, S TI Measurement of the t(t)over-bar production cross section in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID TOP-QUARK PRODUCTION; SILICON VERTEX DETECTOR; (P)OVER-BAR-P COLLISIONS; HADRONIC COLLISIONS; COLLIDER DETECTOR; FERMILAB; Q(Q)OVER-BAR->T(B)OVER-BAR; PHYSICS AB We present a measurement of the t (t) over bar production cross section in p (p) over bar collisions at root s = 1.8 TeV using an integrated luminosity of 109 pb(-1) collected with the Collider Detector at Fermilab. The measurement uses t (t) over bar decays into final states which contain one or two high transverse momentum leptons and multiple jets, and final states which contain only jets. Using acceptances appropriate for atop quark mass of 175 GeV/c(2), we find sigma(ii) = 7.6(-1.5)(+1.8) pg. C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Michigan, Ann Arbor, MI 48109 USA. MIT, Cambridge, MA 02139 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, I-35132 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Univ Rochester, New York, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Peters, Michael/B-4973-2009; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 25 TC 56 Z9 56 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2773 EP 2778 DI 10.1103/PhysRevLett.80.2773 PG 6 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000006 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Baccehtta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Chigangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Nakano, I Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Likens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Meguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, P Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Baccehtta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Chlebana, F Christofek, L Chu, ML Chigangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Erdmann, W Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Frisch, H Fukui, Y Gadomski, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Huth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kongeter, A Kondo, K Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E Kurino, K Kuwabara, T Laasanen, AT Nakano, I Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Likens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Meguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Nomerotski, A Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, P Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S CA CDF Collaboration TI Measurement of the top quark mass and t(t)over-bar production cross section from dilepton events at the collider detector at Fermilab SO PHYSICAL REVIEW LETTERS LA English DT Article ID (P)OVER-BAR-P COLLISIONS AB We present an analysis of dilepton events originating from t(t)over-bar production in p(p)over-bar collisions at root s = 1.8 TeV at the Fermilab Tevatron Collider. The sample corresponds to an integrated luminosity of 109 +/- 7 pb(-1). We observe nine candidate events, with an estimated background of 2.4 +/- 0.5 events. M-top = 161 +/- 17(stat) +/- 10(syst) GeV/c(2). We determine the mass of the top quark to be M-top = 161 +/- 17(stat) +/- 10(syst) GeV/c(2). In addition, we measure a t(t)over-bar production cross section of 8.2(-3.4)(+4.4) pb (where M-top = 175 GeV/c(2) has been assumed for the acceptance estimate). C1 Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, I-35131 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Abe, F (reprint author), Kek Nat Lab High Energy Phys, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Nomerotski, Andrei/A-5169-2010; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Azzi, Patrizia/H-5404-2012; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014; OI Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Azzi, Patrizia/0000-0002-3129-828X; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; Gallinaro, Michele/0000-0003-1261-2277; Turini, Nicola/0000-0002-9395-5230 NR 16 TC 86 Z9 86 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2779 EP 2784 DI 10.1103/PhysRevLett.80.2779 PG 6 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000007 ER PT J AU Dunn, J Osterheld, AL Shepherd, R White, WE Shlyaptsev, VN Stewart, RE AF Dunn, J Osterheld, AL Shepherd, R White, WE Shlyaptsev, VN Stewart, RE TI Demonstration of x-ray amplification in transient gain nickel-like palladium scheme SO PHYSICAL REVIEW LETTERS LA English DT Article ID XUV LASER; DRIVEN AB We report experimental results of x-ray amplification of spontaneous emission in a Ni-like transient collisional excitation scheme. The Ni-like plasma formation, ionization, and collisional excitation requires irradiation of a slab target by two laser pulses: a formation beam with 5 J energy of 800 ps duration and a pump beam of 5 J energy in 1.1 ps. A gain of 35 cm(-1) and a gL product of 12.5 are measured on the 4d --> 4p J = 0 --> 1 transition for Ni-like Pd at 147 Angstrom with an 8 mm line focus. The high efficiency of this scheme at "table-top" laser energies is a direct consequence of the nonstationary population inversion produced by the high intensity picosecond pulse. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. PN Lebedev Phys Inst, Moscow 117924, Russia. RP Dunn, J (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 30 TC 214 Z9 220 U1 2 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2825 EP 2828 DI 10.1103/PhysRevLett.80.2825 PG 4 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000018 ER PT J AU Glenzer, SH Suter, LJ Turner, RE MacGowan, BJ Estabrook, KG Blain, MA Dixit, SN Hammel, BA Kauffman, RL Kirkwood, RK Landen, OL Monteil, MC Moody, JD Orzechowski, TJ Pennington, DM Stone, GF Weiland, TL AF Glenzer, SH Suter, LJ Turner, RE MacGowan, BJ Estabrook, KG Blain, MA Dixit, SN Hammel, BA Kauffman, RL Kirkwood, RK Landen, OL Monteil, MC Moody, JD Orzechowski, TJ Pennington, DM Stone, GF Weiland, TL TI Energetics of inertial confinement fusion Hohlraum plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID LASER-BEAM DEFLECTION; NATIONAL-IGNITION-FACILITY; X-RAY CONFINEMENT; INDIRECTLY DRIVEN; LIGHT; SYMMETRY; FILAMENTATION; TEMPERATURES; TARGETS; DESIGN AB We present the first measurements of radiation temperatures and stimulated scattering losses in laser-driven, gas-filled hohlraums. They show efficient coupling when applying laser beam smoothing techniques. Scattering losses are reduced to the 3% level while the radiation temperatures increased by similar to 15 eV for smoothed laser beams. We observe peak radiation temperatures in excess of 230 eV in gas-filled hohlraums consistent with detailed hydrodynamic LASNEX modeling. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Ctr Etud Limeil Valenton, F-94195 Villeneuve St Georges, France. RP Glenzer, SH (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-399, Livermore, CA 94551 USA. NR 37 TC 51 Z9 52 U1 2 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2845 EP 2848 DI 10.1103/PhysRevLett.80.2845 PG 4 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000023 ER PT J AU Pohl, K Cho, JH Terakura, K Scheffler, M Plummer, EW AF Pohl, K Cho, JH Terakura, K Scheffler, M Plummer, EW TI Anomalously large thermal expansion at the (0001) surface of beryllium without observable interlayer anharmonicity SO PHYSICAL REVIEW LETTERS LA English DT Article ID LEED; NI(001) AB We have measured a large thermal surface expansion, 6 times larger than the bulk, on Be(0001) using low-energy electron diffraction. This observation seems to be inconsistent with previous measurements reporting negligible anharmonicity in the surface phonon modes normal to the surface. Density-functional theory calculations for the thermal expansion from the minimum in the free energy within the quasiharmonic approximation agree with the experimental observations and demonstrate that the enhanced thermal expansion is caused largely by a softening of the in-plane vibrations. C1 Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. JRCAT, Natl Inst Adv Interdisciplinary Res, Tsukuba, Ibaraki 305, Japan. Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. RP Pohl, K (reprint author), Oak Ridge Natl Lab, Div Solid State, POB 2008, Oak Ridge, TN 37831 USA. RI Scheffler, Matthias/O-4649-2016; Cho, Jun-Hyung/R-7256-2016 OI Cho, Jun-Hyung/0000-0002-1785-1835 NR 33 TC 49 Z9 49 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2853 EP 2856 DI 10.1103/PhysRevLett.80.2853 PG 4 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000025 ER PT J AU Rotenberg, E Kevan, SD AF Rotenberg, E Kevan, SD TI Evolution of Fermi level crossings versus H coverage on W(110) SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; SURFACE; HYDROGEN; RECONSTRUCTION; TUNGSTEN; PHONONS AB Two-dimensional Fermi contours of clean and hydrogen-induced surface electronic states have been systematically measured vs coverage of H on W(110) using angle-resolved photoemission. We observe a new pair of spin-orbit-interaction-split surface states, whose splitting grows systematically with hydrogen coverage and whose Fermi contours are strongly nested due to their opposing curvatures. Momentum-dependent electronic transitions between these states drive two previously observed anomalous behaviors: The phonon anomalies along <(Gamma H)over bar> and <(Gamma S)over bar> observed with inelastic helium scattering and electron energy loss spectroscopy, and the shifted-upper-layer reconstruction observed by low-energy electron diffraction for coverages greater than 0.5 monolayer. C1 Univ Oregon, Dept Phys, Eugene, OR 97403 USA. RP Rotenberg, E (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, MS 2-400, Berkeley, CA 94720 USA. RI Rotenberg, Eli/B-3700-2009; Kevan, Stephen/F-6415-2010 OI Rotenberg, Eli/0000-0002-3979-8844; Kevan, Stephen/0000-0002-4621-9142 NR 22 TC 64 Z9 64 U1 2 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 30 PY 1998 VL 80 IS 13 BP 2905 EP 2908 DI 10.1103/PhysRevLett.80.2905 PG 4 WC Physics, Multidisciplinary SC Physics GA ZE093 UT WOS:000072757000038 ER PT J AU Moore, DS Ure, TAM Butler, LRP AF Moore, DS Ure, TAM Butler, LRP TI Nomenclature, symbols, units and their usage in spectrochemical analysis - Cumulative index of terms: Parts I-XIII SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article C1 Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, Los Alamos, NM 87545 USA. Univ Strathclyde, Dept Pure & Appl Chem, Glasgow G1 1XL, Lanark, Scotland. RP Moore, DS (reprint author), Univ Calif Los Alamos Natl Lab, Chem Sci & Technol Div, POB 1663, Los Alamos, NM 87545 USA. NR 0 TC 1 Z9 1 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD MAR 30 PY 1998 VL 53 IS 3 BP 379 EP 397 DI 10.1016/S0584-8547(98)00113-X PG 19 WC Spectroscopy SC Spectroscopy GA ZW411 UT WOS:000074408300001 ER PT J AU Ciocan, AC Mao, XL Borisov, OV Russo, RE AF Ciocan, AC Mao, XL Borisov, OV Russo, RE TI Optical emission spectroscopy studies of the influence of laser ablated mass on dry inductively coupled plasma conditions SO SPECTROCHIMICA ACTA PART B-ATOMIC SPECTROSCOPY LA English DT Article DE laser ablation; ICP-AES; dry plasma; plasma temperature; plasma diagnostics ID ELECTRON NUMBER DENSITIES; GAS-FLOW RATE; ATOMIC EMISSION; SOLID SAMPLES; SPECTROMETRY; TEMPERATURE; ICP; DIAGNOSTICS; SCATTERING; INTENSITY AB The amount of ablated mass can influence the temperature and excitation characteristics of the inductively coupled plasma (ICP) and must be taken into account to ensure accurate chemical analysis. The ICP electron number density was investigated by using measurements of the Mg ionic to atomic resonant-line ratios during laser ablation of an aluminum matrix. The ICP excitation temperature was measured by using selected Fe lines during laser ablation of an iron matrix. A Nd:YAG laser (3 ns pulse duration) at 266 nm was used for these ablation-sampling studies. Laser energy, power density, and repetition rate were varied in order to change the quantity of ablated mass into the ICP. Over the range of laser operating conditions studied herein, the ICP was not significantly influenced by the quantity of solid sample. Therefore, analytical measurements can be performed accurately and fundamental studies of laser ablation processes (such as ablation mass roll-off, fractional vaporization) can be investigated using inductively coupled plasma-atomic emission spectroscopy (ICP-AES). (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Russo, RE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 31 TC 13 Z9 15 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 0584-8547 J9 SPECTROCHIM ACTA B JI Spectroc. Acta Pt. B-Atom. Spectr. PD MAR 30 PY 1998 VL 53 IS 3 BP 463 EP 470 DI 10.1016/S0584-8547(97)00130-4 PG 8 WC Spectroscopy SC Spectroscopy GA ZW411 UT WOS:000074408300007 ER PT J AU Pieksma, M Ovchinnikov, SY Macek, JH AF Pieksma, M Ovchinnikov, SY Macek, JH TI Radial-decoupling excitation mechanism in slow atomic collisions studied using zero-range model potentials SO JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS LA English DT Article ID SADDLE-POINT ELECTRONS; ANGULAR-DISTRIBUTION; IONIZATION; HYDROGEN; HE AB One-dimensional zero-range model potentials are employed to investigate the recently proposed radial-decoupling excitation mechanism in ion-atom collisions. The expression for the total (i.e. excitation plus ionization) radial-decoupling probability, obtained in the adiabatic limit, agrees with the result of our earlier, tentative approach (Pieksma and Ovchinnikov 1994 J. Phys. B: At. Mel. Opt. Phys. 27 4573) to second order in the collision velocity v. In fact, at low collision energies the cross section just scales with v(2). This is in accordance with the adiabatic theorem as formulated by Born and Fock (1928 Z. Phys. 51 165), which also implies a power law for the cross section as the collision velocity becomes sufficiently low. The v(2) dependence is a purely quantal effect, and it is argued that it represents the correct low-energy cross section behaviour, even though it seems to contradict the exponential law that follows from the conventional theory of adiabatic transitions. C1 Univ Utrecht, Debye Inst, Dept Atom & Interface Phys, NL-3508 GA Utrecht, Netherlands. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. AF Ioffe Phys Tech Inst, St Petersburg 194021, Russia. RP Pieksma, M (reprint author), Univ Utrecht, Debye Inst, Dept Atom & Interface Phys, POB 80000, NL-3508 GA Utrecht, Netherlands. RI Ovchinnikov, Serguei/C-4994-2014; Institute (DINS), Debye/G-7730-2014 NR 36 TC 8 Z9 8 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-4075 J9 J PHYS B-AT MOL OPT JI J. Phys. B-At. Mol. Opt. Phys. PD MAR 28 PY 1998 VL 31 IS 6 BP 1267 EP 1278 DI 10.1088/0953-4075/31/6/013 PG 12 WC Optics; Physics, Atomic, Molecular & Chemical SC Optics; Physics GA ZF958 UT WOS:000072950300013 ER PT J AU Muller, R AF Muller, R TI Lifeline - Richard Muller SO LANCET LA English DT Editorial Material C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Muller, R (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU LANCET LTD PI LONDON PA 42 BEDFORD SQUARE, LONDON WC1B 3SL, ENGLAND SN 0140-6736 J9 LANCET JI Lancet PD MAR 28 PY 1998 VL 351 IS 9107 BP 996 EP 996 PG 1 WC Medicine, General & Internal SC General & Internal Medicine GA ZE227 UT WOS:000072770900070 ER PT J AU Hori, CE Permana, H Ng, KYS Brenner, A More, K Rahmoeller, KM Belton, D AF Hori, CE Permana, H Ng, KYS Brenner, A More, K Rahmoeller, KM Belton, D TI Thermal stability of oxygen storage properties in a mixed CeO2-ZrO2 system SO APPLIED CATALYSIS B-ENVIRONMENTAL LA English DT Article DE ceria; zirconia; cerium oxide; zirconium oxide; solid solution; oxygen storage; platinum ID SOLID-SOLUTIONS; CATALYSTS; CAPACITY; OXIDE; REDUCTION; CERIA AB CeO2 and CeO2/ZrO2 supports were prepared by two low temperature (500 degrees C) routes: calcination of hydroxide precipitates and firing mixtures of acetates. The supports were loaded with 0.5% Pt and characterized both fresh and aged (at 800 and 1000 degrees C). X-ray diffraction analyses show that a CeO2/ZrO2 solid solution is formed in the samples prepared by precipitation of the hydroxides and calcination at 500 degrees C. To our knowledge this is the lowest temperature chemical route (not including high energy ball milling) to CeO2/ZrO2 solid solutions yet reported. Samples prepared by firing the acetate mixtures had almost exclusively CeO2 and ZrO2 in separated phases. Oxygen storage measurements showed that the addition of zirconia increased the oxygen storage capacities (on a per gram of catalyst basis) over ceria alone for both preparation methods. In the phase separated materials the amount of reversibly stored oxygen was 1.7-2.5 times more per gram catalyst than that of ceria only. The beneficial effects of zirconia are most pronounced in the solid solutions which had oxygen storage 3-5 times higher than ceria. When the Zr concentration is optimized, the solid solution materials aged at 1000 degrees C showed higher oxygen storage than fresh CeO2. For both preparation methods, the optimal (per gram catalyst) Zr concentration was found to be 25 mol% Zr for samples aged at 1000 degrees C, however, the performance of the solid solution materials was somewhat insensitive to Zr loading between 15 and 50 mol% Zr. (C) 1998 Elsevier Science B.V. C1 Gen Motors Res & Dev Ctr, Dept Phys & Phys Chem, Warren, MI 48090 USA. Wayne State Univ, Dept Chem Engn, Detroit, MI 48202 USA. Wayne State Univ, Dept Chem, Detroit, MI 48202 USA. Oak Ridge Natl Lab, High Temp Mat Lab, Oak Ridge, TN 37831 USA. RP Belton, D (reprint author), Gen Motors Res & Dev Ctr, Dept Phys & Phys Chem, Warren, MI 48090 USA. EM dbelton@cmsa.gmr.com RI More, Karren/A-8097-2016; OI More, Karren/0000-0001-5223-9097; Ng, K Y Simon/0000-0002-7578-487X NR 17 TC 396 Z9 434 U1 17 U2 144 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0926-3373 J9 APPL CATAL B-ENVIRON JI Appl. Catal. B-Environ. PD MAR 27 PY 1998 VL 16 IS 2 BP 105 EP 117 DI 10.1016/S0926-3373(97)00060-X PG 13 WC Chemistry, Physical; Engineering, Environmental; Engineering, Chemical SC Chemistry; Engineering GA ZG485 UT WOS:000073008400002 ER PT J AU McCune, W AF McCune, W TI Automatic proofs and counterexamples for some ortholattice identities SO INFORMATION PROCESSING LETTERS LA English DT Article DE automatic theorem proving; ortholattice; quantum logic; theory of computation AB This note answers questions on whether three identities known to hold for orthomodular lattices are true also for ortholattices. One identity is shown to fail by MACE, a program that searches for counterexamples, and the other two are proved to hold by EQP, an equational theorem prover. The problems, from work in quantum logic, were given to us by Norman Megill. (C) 1998 Elsevier Science B.V. C1 Argonne Natl Lab, Math & Comp Sci div, Argonne, IL 60439 USA. RP McCune, W (reprint author), Argonne Natl Lab, Math & Comp Sci div, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 10 TC 5 Z9 6 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0020-0190 J9 INFORM PROCESS LETT JI Inf. Process. Lett. PD MAR 27 PY 1998 VL 65 IS 6 BP 285 EP 291 DI 10.1016/S0020-0190(98)00015-5 PG 7 WC Computer Science, Information Systems SC Computer Science GA ZL120 UT WOS:000073400800001 ER PT J AU Whalen, JM Lucier, GM Chacon, L Bartlett, N AF Whalen, JM Lucier, GM Chacon, L Bartlett, N TI The room temperature conversion of nickel difluoride to hexafluoronickelate(IV) salts of alkali cations SO JOURNAL OF FLUORINE CHEMISTRY LA English DT Article DE room temperature conversion; nickel difluoride; alkali cations ID FLUORIDES AB NiF2 was oxidized at similar to 20 degrees C, to NiF62- by sunlight- or ultraviolet light-irradiated F-2 in liquid anhydrous hydrogen fluoride (aHF) containing alkali hydrofluorides {AF(HF)(x)}. Quantitative formation of NiF62- can be achieved with strongly basic solutions (e.g., KF:HF molar ratio similar to 1:4). Li2NiF6, which was previously unknown, is the least aHF soluble of the alkali NiF62- salts, and was prepared in high purity. (C) 1998 Elsevier Science S.A. All rights reserved. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Whalen, JM (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. NR 23 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0022-1139 J9 J FLUORINE CHEM JI J. Fluor. Chem. PD MAR 27 PY 1998 VL 88 IS 2 BP 107 EP 110 DI 10.1016/S0022-1139(98)00105-5 PG 4 WC Chemistry, Inorganic & Nuclear; Chemistry, Organic SC Chemistry GA ZF769 UT WOS:000072931300002 ER PT J AU Doran, JC Hubbe, JM Liljegren, JC Shaw, WJ Collatz, GJ Cook, DR Hart, RL AF Doran, JC Hubbe, JM Liljegren, JC Shaw, WJ Collatz, GJ Cook, DR Hart, RL TI A technique for determining the spatial and temporal distributions of surface fluxes of heat and moisture over the Southern Great Plains Cloud and Radiation Testbed SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID PARAMETERIZATION SIB2; STOMATAL CONDUCTANCE; ATMOSPHERIC GCMS; BOUNDARY-LAYER; LAND; MODEL; PHOTOSYNTHESIS; EXCHANGE; PROJECT; CLIMATE AB Land surface parameterization schemes such as the Simple Biosphere Model (SiB2) have found considerable use in climate simulation models, where they provide lower boundary conditions in the form of surface sensible and latent heat fluxes. A methodology is described to apply models of this type at high resolution, using data from the Department of Energy's Cloud and Radiation Testbed in Oklahoma and Kansas, to determine the spatial variations of heat fluxes over the domain and to determine area-weighted flux averages for use in single-column model studies. Data from a dense array of meteorological instruments are interpolated to provide the wind, temperature, vapor pressure, radiation, and precipitation values needed by SiB2. The state of the vegetation is characterized through the use of the normalized difference vegetation index determined from satellites. The performance of the SiB2 model is evaluated by comparing its predictions with flux data from seven Bowen ratio stations over a B-month period. No tuning of the model parameters for individual sites was allowed during the simulation period. Although there is significant scatter in the results, the performance of the model was generally good, accounting for over 60% of the variance in sensible heat fluxes and over 80% of the variance in latent heat fluxes'. The model was therefore used to prepare "flux maps" for the study area. These maps show large contrasts in sensible and latent heat fluxes associated primarily with differences in vegetation cover and soil moisture over the site. The differences in vegetation, in turn, result from the planting of large areas with winter wheat, which leaves some regions nearly devoid of actively growing vegetation in midsummer, while other areas are still covered with thriving crops or naturally occurring vegetation. Implications for determining large-area averages of fluxes from a limited number of measurement sites are discussed. C1 Pacific NW Lab, Richland, WA 99352 USA. NASA, Goddard Space Flight Ctr, Biospher Sci Branch, Greenbelt, MD 20771 USA. Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. Iowa State Univ, IPRT, Ctr Nondestruct Evaluat, Ames, IA 50011 USA. RP Doran, JC (reprint author), Pacific NW Lab, POB 999,MSIN K9-30, Richland, WA 99352 USA. EM jc_doran@pnl.gov; jm_hubbe@pnl.gov; jim@ultra1.cnde.iastate.edu; will.shaw@pnl.gov; jcollatz@biome.gsfc.nasa.gov; cook@anler.er.anl.gov; hart@anler.er.anl.gov RI collatz, george/D-5381-2012 NR 23 TC 27 Z9 30 U1 0 U2 2 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 27 PY 1998 VL 103 IS D6 BP 6109 EP 6121 DI 10.1029/97JD03427 PG 13 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZD911 UT WOS:000072737800014 ER PT J AU Abdul-Razzak, H Ghan, SJ Rivera-Carpio, C AF Abdul-Razzak, H Ghan, SJ Rivera-Carpio, C TI A parameterization of aerosol activation - 1. Single aerosol type SO JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES LA English DT Article ID ANTHROPOGENIC AEROSOLS; CONDENSATION; SIZE AB This paper presents a parameterization of the fraction of aerosol particles activated to form cloud droplets in a parcel of air rising adiabatically. The study applies to aerosols of a single lognormal size distribution with uniform chemical composition and capable of serving as cloud condensation nuclei. The parameterization is based on analysis of the rate equations for the parcel supersaturation and aerosol activation process. The analysis leads to the identification of only four dimensionless parameters on which the fraction of activation strongly depends. Using results of detailed numerical simulations by a size-resolving Lagrangian parcel model, errors due to simplifying assumptions used in the analysis were largely eliminated by employing adjustment coefficients. For a wide range of governing parameters (e.g., particle radius, standard deviation, updraft velocity, etc.), differences between the parametric equations and the numerical model results are less than 10% for most conditions and less than 25% for some extreme but realistic conditions. This new parameterization is significantly more accurate and successful in representing the fraction of activation in terms of governing parameters than any known parameterization. C1 Texas A&M Univ, Dept Mech & Ind Engn, Kingsville, TX 78363 USA. Pacific NW Lab, Richland, WA 99352 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Abdul-Razzak, H (reprint author), Texas A&M Univ, Dept Mech & Ind Engn, Campus Box 191, Kingsville, TX 78363 USA. RI Ghan, Steven/H-4301-2011 OI Ghan, Steven/0000-0001-8355-8699 NR 32 TC 118 Z9 118 U1 0 U2 21 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-897X J9 J GEOPHYS RES-ATMOS JI J. Geophys. Res.-Atmos. PD MAR 27 PY 1998 VL 103 IS D6 BP 6123 EP 6131 PG 9 WC Meteorology & Atmospheric Sciences SC Meteorology & Atmospheric Sciences GA ZD911 UT WOS:000072737800015 ER PT J AU Khrebtukov, DB Macek, JH AF Khrebtukov, DB Macek, JH TI Harmonic oscillator Green functions SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article AB The Green function for the Schrodinger equation with an isotropic, three-dimensional harmonic-oscillator potential is given in closed form. A similar closed form is obtained when the Schrodinger equation also contains a magnetic interaction and the magnetic field is such that the precession and oscillation frequencies are equal. The latter Green function is used to obtain energy and Sturmian eigenvalues that occur in the theory of atom-atom collisions. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Khrebtukov, DB (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. NR 12 TC 9 Z9 10 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD MAR 27 PY 1998 VL 31 IS 12 BP 2853 EP 2868 DI 10.1088/0305-4470/31/12/010 PG 16 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA ZF966 UT WOS:000072951100010 ER PT J AU Greathouse, J Sposito, G AF Greathouse, J Sposito, G TI Monte Carlo and molecular dynamics studies of interlayer structure in Li(H(2)O)(3)-smectites SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID SWELLING CLAY-MINERALS; COMPUTER-SIMULATION; AB-INITIO; WATER; MONTMORILLONITE; MECHANISM; SMECTITES; LI+ AB Monte Carlo and molecular dynamics simulations were performed to elucidate interlayer structure in hydrated Li-smectites (hectorite, beidellite, or montmorillonite with interlayer Li(+)) at low water content (H(2)O/Li = 3). Previous spectroscopic studies of these stable clay mineral hydrates have led to interlayer structural models based on a postulated inner-sphere surface complex comprising Lit bound directly to the smectite surface while surmounted by exactly three solvating water molecules that execute hindered rotational motions. Our simulation results, based on tested water-water, Li(+)-water, water-clay mineral, and Li(+)-clay mineral potential functions, showed that the nature of the interlayer Li(+) solvation complexes in fact depends critically on the location of negative charge sites within the smectite layers. Inner-sphere surface complexes were observed to form exclusively on Li-beidellite (tetrahedral charge sites), outer-sphere surface complexes formed exclusively on Li-hectorite (octahedral charge sites), and both types of surface complex formed on Li-montmorillonite, which also contains bath types of charge site. The Li(+) solvation number in these clay hydrates can vary from two to four. Rotational motions of the water molecules solvating Li(+) occurred (on a picosecond time scale) only if inner-sphere surface complexes had formed, again strongly contradicting the spectroscopic models. Improvement of these models and the spectroscopic data is needed to resolve the major differences between our simulation predictions and the current experimental interpretations of interlayer structure on Li(H(2)O)(3)-smectites. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Berkeley, CA 94720 USA. Univ Incarnate Word, Dept Chem, San Antonio, TX 78209 USA. RP Greathouse, J (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Earth Sci, Mail Stop 90-1116, Berkeley, CA 94720 USA. EM greathou@universe.uiwtx.edu NR 34 TC 55 Z9 55 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 26 PY 1998 VL 102 IS 13 BP 2406 EP 2414 DI 10.1021/jp980120h PG 9 WC Chemistry, Physical SC Chemistry GA ZF505 UT WOS:000072904200017 ER PT J AU Murphy, KD Lee, CL AF Murphy, KD Lee, CL TI The 1 : 1 internally resonant response of a cantilever beam attached to a rotating body SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID FLEXIBLE BEAMS; MOVING BASE; DYNAMICS; OSCILLATIONS; MOTIONS AB Modal coupling in the dynamics of a cantilever beam attached to a rotating body is investigated using a coupled, non-linear three-degree-of-freedom model which includes the effects of centrifugal stiffening. The near-resonant response of two lateral modes (one in-plane and one out-of-plane as defined by the plane of rotation) driven by a periodic out-of-plane excitation is examined for the case in which the natural frequencies of the lateral modes are commensurate in a near one-to-one ratio. The existence and stability of periodic solutions are examined using a second order perturbation analysis. Regions in the system parameter space are identified where single-or multi-mode responses may occur. Typical responses involve Hopf, saddle node and pitchfork bifurcations. (C) 1998 Academic Press Limited. C1 Univ Connecticut, Dept Engn Mech, Storrs, CT 06269 USA. Univ Calif Lawrence Livermore Natl Lab, Struct Mech Grp, Livermore, CA 94551 USA. RP Murphy, KD (reprint author), Univ Connecticut, Dept Engn Mech, Storrs, CT 06269 USA. NR 16 TC 6 Z9 6 U1 0 U2 5 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD MAR 26 PY 1998 VL 211 IS 2 BP 179 EP 194 DI 10.1006/jsvi.1997.1341 PG 16 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA ZG303 UT WOS:000072987500003 ER PT J AU Deckert, G Warren, PV Gaasterland, T Young, WG Lenox, AL Graham, DE Overbeek, R Snead, MA Keller, M Aujay, M Huber, R Feldman, RA Short, JM Olsen, GJ Swanson, RV AF Deckert, G Warren, PV Gaasterland, T Young, WG Lenox, AL Graham, DE Overbeek, R Snead, MA Keller, M Aujay, M Huber, R Feldman, RA Short, JM Olsen, GJ Swanson, RV TI The complete genome of the hyperthermophilic bacterium Aquifex aeolicus SO NATURE LA English DT Article ID HYDROGEN-OXIDIZING BACTERIA; FACTOR-BASED VECTOR; ESCHERICHIA-COLI; NUCLEOTIDE-SEQUENCE; HUMAN DNA; SP-NOV; GENE; PYROPHILUS; EXPRESSION; PROTEINS AB Aquifex aeolicus was one of the earliest diverging, and is one of the most thermophilic, bacteria known. It can grow on hydrogen, oxygen, carbon dioxide, and mineral salts. The complex metabolic machinery needed for A. aeolicus to function as a chemolithoautotroph (an organism which uses an inorganic carbon source for biosynthesis and an inorganic chemical energy source) is encoded within a genome that is only one-third the size of the E, coli genome, Metabolic flexibility seems Po be reduced as a result of the limited genome size, The use of oxygen (albeit at very low concentrations) as an electron acceptor is allowed by the presence of a complex respiratory apparatus. Although this organism grows at 95 degrees C, the extreme thermal limit of the Bacteria, only a few specific indications of thermophily are apparent from the genome. Here we describe the complete genome sequence of 1,551,335 base pairs of this evolutionarily and physiologically interesting organism. C1 Diversa Corp, San Diego, CA 92121 USA. Argonne Natl Lab, Div Math & Comp Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Microbiol, Urbana, IL 61801 USA. Univ Regensburg, Lehrstuhl Mikrobiol, D-8400 Regensburg, Germany. RP Swanson, RV (reprint author), Diversa Corp, 10665 Sorrento Valley Rd, San Diego, CA 92121 USA. RI Graham, David/F-8578-2010; Keller, Martin/C-4416-2012; OI Graham, David/0000-0001-8968-7344; Swanson, Ronald/0000-0002-6486-2676 NR 49 TC 853 Z9 1655 U1 3 U2 42 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAR 26 PY 1998 VL 392 IS 6674 BP 353 EP 358 PG 14 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZD694 UT WOS:000072713600041 PM 9537320 ER PT J AU Daehnick, WW Flammang, RW Dytman, SA Tedeschi, DJ Thompson, RA Vrana, T Foster, CC Hardie, JG Jacobs, WW Rinckel, T Stephenson, EJ Pancella, PV Brooks, WK AF Daehnick, WW Flammang, RW Dytman, SA Tedeschi, DJ Thompson, RA Vrana, T Foster, CC Hardie, JG Jacobs, WW Rinckel, T Stephenson, EJ Pancella, PV Brooks, WK TI Analyzing powers in (p)over-right-arrow-p -> pn pi(+) and determination of pion S and P wave amplitudes near threshold SO PHYSICS LETTERS B LA English DT Article ID REACTION NEAR-THRESHOLD; TOTAL CROSS-SECTION; PP->PP-PI(0); EXCHANGE; P+P->P+P+PI-0; NN->D-PI AB Analyzing powers were measured and used to quantify the observation that a-wave processes dominate near threshold. Values of A(gamma)(theta(pi),phi(pi) = 0 degrees) are presented for eta values of 0.22, 0.42 and 0.50. Maximum analyzing powers A(N0) are equal to -0.13, -0.24, and -0.28, respectively. A partial wave analysis, made possible by the new analyzing powers and available cross sections, indicates that the a-wave contribution to the cross section constitutes about 91% of the total cross section at eta = 0.22, or 300 MeV. It decreases to about 75% for eta = 0.5. (C) 1998 Elsevier Science B.V. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Indiana Univ, Cyclotron Facil, Bloomington, IN 47405 USA. Western Michigan Univ, Dept Phys, Kalamazoo, MI 49008 USA. Thomas Jefferson Natl Accelerator Facil, Newport News, VA 23606 USA. RP Daehnick, WW (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. RI Brooks, William/C-8636-2013 OI Brooks, William/0000-0001-6161-3570 NR 36 TC 13 Z9 13 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 26 PY 1998 VL 423 IS 3-4 BP 213 EP 218 DI 10.1016/S0370-2693(98)00079-3 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZM231 UT WOS:000073517800001 ER PT J AU Nir, Y Worah, MP AF Nir, Y Worah, MP TI Probing the flavor and CP structure of supersymmetric models with K ->pi nu(nu)over-bar decays SO PHYSICS LETTERS B LA English DT Article ID STANDARD-MODEL; B-DECAYS; HORIZONTAL SYMMETRIES; CKM MATRIX; TOP-QUARK; SUPERGRAVITY; CONSTRAINTS; BREAKING; MASS AB We study the implications of various supersymmetric models on the rare K+ --> and K-L --> decays. Although large effects are possible in generic supersymmetric models, most of the known supersymmetric flavor models lead to negligible effects. Thus, it is likely that one can get information about CKM matrix elements from these decays even in the presence of supersymmetry. Moreover, the possibility of large contributions to K --> in generic supersymmetry models can be constrained by improved bounds on D - (D) over bar mixing. We show that it may be possible to distinguish between different supersymmetric flavor models by combining the information from the K --> decays with that from B - (B) over bar and D - (D) over bar mixing. (C) 1998 Elsevier Science B.V. C1 Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Nir, Y (reprint author), Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. NR 37 TC 54 Z9 54 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 26 PY 1998 VL 423 IS 3-4 BP 319 EP 326 DI 10.1016/S0370-2693(98)00098-7 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZM231 UT WOS:000073517800016 ER PT J AU Kolb, EW Riotto, A Tkachev, II AF Kolb, EW Riotto, A Tkachev, II TI GUT baryogenesis after preheating: numerical study of the production and decay of X-bosons SO PHYSICS LETTERS B LA English DT Article ID INFLATIONARY UNIVERSE; BARYON ASYMMETRY AB We perform a fully non-linear calculation of the production of supermassive Grand Unified Theory (GUT) X bosons during preheating, taking into account the fact that they are unstable with a decay width Gamma(X). We show that parametric resonance does not develop if Gamma(X) is larger than about 10(-2)m(X). We compute the nonthermal number density of superheavy bosons produced in the preheating phase and demonstrate that the observed baryon asymmetry may be explained by GUT baryogenesis after preheating if Gamma(X) is smaller than about 10(-3)m(X). (C) 1998 Published by Elsevier Science B.V. C1 NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. Univ Chicago, Dept Astron & Astrophys, Enrico Fermi Inst, Chicago, IL 60637 USA. CERN, Div Theory, CH-1211 Geneva, Switzerland. Purdue Univ, Dept Phys, W Lafayette, IN 47907 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RP Kolb, EW (reprint author), NASA, Fermi Natl Accelerator Lab, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. EM rocky@rigolelto.fnal.gov; riotto@nxth04.cern.ch; tkachev@physics.purdue.edu NR 24 TC 71 Z9 71 U1 2 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 26 PY 1998 VL 423 IS 3-4 BP 348 EP 354 DI 10.1016/S0370-2693(98)00134-8 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZM231 UT WOS:000073517800019 ER PT J AU Belyaev, VM Johnson, MB AF Belyaev, VM Johnson, MB TI Pion light-cone wave functions and light-front quark model SO PHYSICS LETTERS B LA English DT Article ID QCD SUM-RULES; TRANSITION FORM-FACTORS; RELATIVISTIC QUARKS; ASYMPTOTIC-BEHAVIOR; EXCLUSIVE PROCESSES; RESONANCE PHYSICS; DYNAMICS; MESONS; FACTORIZATION AB We discuss a relation between the light-front quark model and QCD. We argue that this model can be used for an evaluation of the Light-cone wave functions for moderate values of u, but that it is inapplicable for this purpose in the region near the end points u = (0,1). We find additional support for a recent analysis in which it was claimed that the twist-two pion wave function attains its asymptotic form. The asymptotic twist-four two-particle wave function is also in good agreement with the light-front quark model. (C) 1998 Published by Elsevier Science B.V. C1 CEA Saclay, SPHT, F-91191 Gif Sur Yvette, France. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Belyaev, VM (reprint author), CEA Saclay, SPHT, F-91191 Gif Sur Yvette, France. NR 32 TC 10 Z9 10 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 26 PY 1998 VL 423 IS 3-4 BP 379 EP 384 DI 10.1016/S0370-2693(98)00152-X PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZM231 UT WOS:000073517800024 ER PT J AU Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmanov, D Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oliveira, E Oltman, E Oshima, N Owen, D Padley, P Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Schaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Steinbruck, G Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Coney, L Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmanov, D Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Manankov, V Mani, S Mao, HS Markeloff, R Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oliveira, E Oltman, E Oshima, N Owen, D Padley, P Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roco, M Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Schaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Steinbruck, G Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A CA DO Collaboration TI Search for the decay b -> X-s mu(+)mu(-) SO PHYSICS LETTERS B LA English DT Article DE FCNC; rare decays; beauty; tevatron ID TRIGGER AB We have searched for the flavor-changing neutral current decay b --> X-s mu(+)mu(-) in collisions at root s = 1.8 TeV with the D0 detector at Fermilab. We determine the 90% confidence level limit for the branching fraction to be B(b --> X-S mu(+)mu(-)) < 3.2 X 10(-4). We argue that this limit is more stringent than the best published limit on this decay rate. (C) 1998 Elsevier Science B.V. C1 NYU, New York, NY 10003 USA. Univ Los Andes, Bogota, Colombia. Univ Arizona, Tucson, AZ 85721 USA. Boston Univ, Boston, MA 02215 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Brown Univ, Providence, RI 02912 USA. Univ Buenos Aires, Buenos Aires, DF, Argentina. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. CINVESTAV, Mexico City 14000, DF, Mexico. Univ Delhi, Delhi 110007, India. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Illinois, Chicago, IL 60607 USA. Indiana Univ, Bloomington, IN 47405 USA. Iowa State Univ, Ames, IA 50011 USA. Korea Univ, Seoul 136701, South Korea. Kyungsung Univ, Pusan 608736, South Korea. Inst Nucl Phys, Krakow, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Moscow State Univ, Moscow, Russia. Univ Nebraska, Lincoln, NE 68588 USA. Northeastern Univ, Boston, MA 02115 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Oklahoma, Norman, OK 73019 USA. Panjab Univ, Chandigarh 160014, India. Inst High Energy Phys, Protvino 142284, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77005 USA. Univ Estado Rio De Janeiro, Rio De Janeiro, Brazil. Univ Rochester, Rochester, NY 14627 USA. CENS, CEA, DAPNIA, Serv Phys Particules, F-91191 Gif Sur Yvette, France. Seoul Natl Univ, Seoul, South Korea. SUNY Stony Brook, Stony Brook, NY 11794 USA. Tata Inst Fundamental Res, Bombay 400005, Maharashtra, India. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Peters, Michael/B-4973-2009; Aihara, Hiroaki/F-3854-2010; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Roe, Natalie/A-8798-2012; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Klyukhin, Vyacheslav/D-6850-2012; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Belyaev, Alexander/F-6637-2015; Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; OI Aihara, Hiroaki/0000-0002-1907-5964; Dudko, Lev/0000-0002-4462-3192; Klyukhin, Vyacheslav/0000-0002-8577-6531; De, Kaushik/0000-0002-5647-4489; Belyaev, Alexander/0000-0002-1733-4408; Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Baarmand, Marc/0000-0002-9792-8619 NR 16 TC 14 Z9 14 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 26 PY 1998 VL 423 IS 3-4 BP 419 EP 426 DI 10.1016/S0370-2693(98)00161-0 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZM231 UT WOS:000073517800029 ER PT J AU Gibson, JK AF Gibson, JK TI Gas-phase transuranium organometallic chemistry: Reactions of Np+, Pu+, NpO+, and PuO+ with alkenes SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID HYDROCARBON ACTIVATION; ELECTRONIC-STRUCTURE; LANTHANIDE CATIONS; MASS-SPECTROMETRY; ION CHEMISTRY; REACTIVITY; COMPLEXES; SC+; UO+; Y+ AB The study of gas-phase organometallic chemistry has been extended to the first two transuranium elements, Np and Pu. Product abundances were determined for reactions of the alkenes, L = ethene, cis-2-butene, cyclohexene, and 1,5-cyclooctadiene (COD), with Np+, NpO+, Pu+, and PuO+, and comparison was made with results for Th+, U+, ThO+, and UO+. A key finding was that U+ and Np+ were comparably effective at dehydrogenation of ethene and 2-butene whereas Pu+ was less effective, consistent with a conventional mechanism of dehydrogenation via oxidative insertion of a prepared "divalent" M+ into a C-H bond (i.e., C-An(+)-H, where An = actinide). The reduced reactivity of Pu+ indicates that its 5f electrons do not participate in C-H bond activation. The smaller discrepancy between U+ and Np+ compared with Pu+ which was found using cyclohexene and COD as reactants can be attributed to their greater polarizabilities and allylic C-H bonds. The linear alkenes were essentially inert toward all of the AnO(+), but cyclohexene was dehydrogenated by UO+ and ThO+ and COD was dehydrogenated by all four AnO(+). With COD, single H-2 loss was dominant for NpO+ and PuO+, while double dehydrogenation was the primary pathway for UO+ and ThO+; it appears that C-H activation occurred by different mechanisms and that the 5f electrons of UO+ may facilitate C-H activation whereas the 5f electrons of NpO+ and PuO+ are inert. The relatively high reactivity of ThO+ accords with the classification of Th as a pseudo-d-block transition element. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Gibson, JK (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. NR 37 TC 38 Z9 38 U1 0 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 25 PY 1998 VL 120 IS 11 BP 2633 EP 2640 DI 10.1021/ja973182e PG 8 WC Chemistry, Multidisciplinary SC Chemistry GA ZD933 UT WOS:000072740300017 ER PT J AU Goguen, PW Xu, T Barich, DH Skloss, TW Song, WG Wang, ZK Nicholas, JB Haw, JF AF Goguen, PW Xu, T Barich, DH Skloss, TW Song, WG Wang, ZK Nicholas, JB Haw, JF TI Pulse-quench catalytic reactor studies reveal a carbon-pool mechanism in methanol-to-gasoline chemistry on zeolite HZSM-5 SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ANGLE-SPINNING NMR; HYDROCARBON FORMATION; DIMETHYL ETHER; CO-REACTION; IN-SITU; PROPENE; SAPO-34 C1 Texas A&M Univ, Lab Magnet Resonance & Mol Sci, College Stn, TX 77843 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Haw, JF (reprint author), Texas A&M Univ, Lab Magnet Resonance & Mol Sci, College Stn, TX 77843 USA. NR 17 TC 104 Z9 107 U1 6 U2 39 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 25 PY 1998 VL 120 IS 11 BP 2650 EP 2651 DI 10.1021/ja973920z PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZD933 UT WOS:000072740300019 ER PT J AU Fernandez, C Lang, DP Amoureux, JP Pruski, M AF Fernandez, C Lang, DP Amoureux, JP Pruski, M TI Measurement of heteronuclear dipolar interactions between quadrupolar and spin-1/2 nuclei in solids by multiple-quantum REDOR NMR SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID ECHO DOUBLE-RESONANCE; MAS; LOCKING; ROTOR; SPINS C1 Ames Lab, Ames, IA 50011 USA. Univ Sci & Technol Lille, CNRS, URA 801, Lab Dynam & Struct Mat Mol, F-59655 Villeneuve Dascq, France. RP Pruski, M (reprint author), Ames Lab, 230 Spedding Hall, Ames, IA 50011 USA. RI fernandez, christian/C-3158-2008 OI fernandez, christian/0000-0002-5476-3148 NR 25 TC 60 Z9 61 U1 0 U2 10 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 25 PY 1998 VL 120 IS 11 BP 2672 EP 2673 DI 10.1021/ja973311r PG 2 WC Chemistry, Multidisciplinary SC Chemistry GA ZD933 UT WOS:000072740300030 ER PT J AU Li, Z Tolan, M Hohr, T Kharas, D Qu, S Sokolov, J Rafailovich, MH Lorenz, H Kotthaus, JP Wang, J Sinha, SK Gibaud, A AF Li, Z Tolan, M Hohr, T Kharas, D Qu, S Sokolov, J Rafailovich, MH Lorenz, H Kotthaus, JP Wang, J Sinha, SK Gibaud, A TI Polymer thin films on patterned Si surfaces SO MACROMOLECULES LA English DT Article ID X-RAY; ROUGH SURFACES AB The propagation of roughness from a patterned silicon surface by polymer thin films was measured as a function of film thickness, time, and surface interaction using atomic force microscopy and synchrotron X-ray reflection. In the presence of an interacting surface, the decay length of the surface modulation was much longer than that observed in simple liquids. By measuring the time dependence of the surface corrugation amplitude, we were able to extract a surface diffusion coefficient by applying a modified version of the Mullins theory for surface diffusion in crystalline solids. The measured diffusion coefficients were an order of magnitude smaller than in the bulk, and scaled as 1/M-3/2, in agreement with previous SIMS results. The results are interpreted in terms of surface interactions confining polymer chains over distances larger than the radii of gyration. C1 SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. Univ Kiel, Inst Expt Phys, D-24098 Kiel, Germany. Univ Munich, Sekt Phys, D-80539 Munich, Germany. Argonne Natl Lab, APS, Argonne, IL 60439 USA. Univ Maine, Fac Sci, F-72017 Le Mans, France. RP Rafailovich, MH (reprint author), SUNY Stony Brook, Dept Mat Sci & Engn, Stony Brook, NY 11794 USA. RI Kotthaus, Jorg/A-7674-2010 NR 24 TC 26 Z9 26 U1 2 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD MAR 24 PY 1998 VL 31 IS 6 BP 1915 EP 1920 DI 10.1021/ma970977x PG 6 WC Polymer Science SC Polymer Science GA ZE039 UT WOS:000072751200028 ER PT J AU Stohr, J Samant, MG Cossy-Favre, A Diaz, J Momoi, Y Odahara, S Nagata, T AF Stohr, J Samant, MG Cossy-Favre, A Diaz, J Momoi, Y Odahara, S Nagata, T TI Microscopic origin of liquid crystal alignment on rubbed polymer surfaces SO MACROMOLECULES LA English DT Article ID MOLECULAR-ORIENTATION; FILMS; DISPLAYS AB Surface-sensitive and polarization-dependent near-edge X-ray absorption fine structure (NEXAFS) measurements clearly reveal a preferred in-plane and out-of-plane orientation of phenyl and C=O groups at the surface of rubbed polyimide films. The unidirectional molecular alignment at the surface is argued to provide the template for liquid crystal (LC) alignment of the films. Both the LC orientation along the rubbing direction as well as the direction of the out-of-plane LC pretilt are explained in a simple model. In this model the LC direction follows the preferential orientation of the phenyl rings at the surface. The preferred phenyl orientation is explained in terms of preferential chain segment alignment through a pulling action of the rubbing cloth fibers. The proposed LC alignment model is based on the existence of a statistically significant unidirectional bond asymmetry at the polymer surface, and it does not require the existence of crystalline order. C1 IBM Corp, Almaden Res Ctr, Div Res, San Jose, CA 95120 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. IBM Japan Ltd, Display Technol, Yamato, Kanagawa 242, Japan. IBM Japan Ltd, Mat Lab, Fujisawa, Kanagawa 252, Japan. RP Stohr, J (reprint author), IBM Corp, Almaden Res Ctr, Div Res, 650 Harry Rd, San Jose, CA 95120 USA. RI Diaz, Javier/F-2381-2016 NR 24 TC 113 Z9 116 U1 1 U2 14 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0024-9297 J9 MACROMOLECULES JI Macromolecules PD MAR 24 PY 1998 VL 31 IS 6 BP 1942 EP 1946 DI 10.1021/ma9711708 PG 5 WC Polymer Science SC Polymer Science GA ZE039 UT WOS:000072751200032 ER PT J AU Wang, JN Nieh, TG AF Wang, JN Nieh, TG TI The role of ledges in creep of TiAl alloys with fine lamellar structures SO ACTA MATERIALIA LA English DT Article ID TITANIUM ALUMINIDES; INTERFACIAL BOUNDARIES; PHASE-TRANSFORMATIONS; ELECTRON-MICROSCOPY; GROWTH-KINETICS; STEPS AB Creep experiments have been conducted on two powder-metallurgy TiAl alloys with fine grains, fine lamellar structures, and compositions of Ti-47Al + 2Cr + 2Nb and Ti-47Al + 2Cr + 1Nb + 1Ta. Results show that the stress exponent n and the activation energy Q decrease with decreasing stress (n similar to 7-9 to 1.5, Q similar to 300 kJ/mol to similar to 150 kJ/mol). Stress reduction led to the occurrence of negative, zero and positive creep at low stresses but only positive creep at high stresses. Thinning and dissolving of alpha(2) lamellae and continuous coarsening of gamma lamellae were observed at both low and high stresses with cross-twinning being a microstructure exclusive at high stresses. To understand the underlying deformation processes, a ledge creep mechanism is proposed. The mechanism involves bunching and escaping of unit-height ledges into or from multiple-height ledges at interfacial boundaries (alpha(2)/gamma and gamma/gamma). It is assumed that the ledge motion, which is diffusion-controlled, causes phase transformation and thus deformation of the sample. Using this mechanism, the experimental results including the stress exponents, activation energies and transient creep behaviors after stress reduction at different stresses are reasonably interpreted. (C) 1998 Beta Metallurgica Inc. C1 Cent S Univ Technol, Powder Met Res Inst, PM Natl Key Lab, Changsha 410083, Hunan, Peoples R China. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Wang, JN (reprint author), Cent S Univ Technol, Powder Met Res Inst, PM Natl Key Lab, Changsha 410083, Hunan, Peoples R China. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 34 TC 62 Z9 62 U1 0 U2 8 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 1887 EP 1901 DI 10.1016/S1359-6454(97)00434-5 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700005 ER PT J AU Peralta, P Laird, C AF Peralta, P Laird, C TI Fatigue fracture at bicrystal interfaces: Experiment and theory SO ACTA MATERIALIA LA English DT Article ID STAGE-I PROPAGATION; HIGH STRAIN FATIGUE; POLYCRYSTALLINE COPPER; CRACK NUCLEATION; SINGLE-CRYSTAL; SLIP PROCESSES; DEPENDENCE; TIP; MECHANISM; FIELDS AB Copper bicrystals dth isoaxial [(1) over bar 49] twist boundaries and a ((1) over bar 49)/(001) "random" boundary were notched at the interface, left or right regarding the slip geometry, and intergranular cracks were propagated under strain control, to study how dislocation structure, crystallography and strain localization affect crack growth. Forward slip at the crack surface was favored regardless of growth direction or misorientation, whereas pre-existent multiple slip around the boundary reduced the dependence of crack kinetics on the growth direction. A model is proposed for intergranular crack growth based on crack tip deformation via crystallographic slip bands and simplifying assumptions about the effects of mode I stress fields on the strain. The experimental and theoretical results, along with published data, provide evidence that an optimal slip geometry exists for fatigue crack propagation. This idea is used to explain experimental results on directional dependence of intergranular cracking of bicrystals, suggesting that the kinematics of deformation has to be considered besides the energetics of dislocation nucleation at a crack tip to explain such results. (C) 1998 Acta Metallurgica Inc. C1 Univ Penn, Dept Mat Sci & Engn, Philadelphia, PA 19104 USA. RP Peralta, P (reprint author), Univ Calif Los Alamos Natl Lab, Ctr Mat Sci, Mail Stop K765, Los Alamos, NM 87545 USA. NR 36 TC 28 Z9 28 U1 2 U2 9 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2001 EP 2020 DI 10.1016/S1359-6454(97)00430-8 PG 20 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700015 ER PT J AU Vaidya, RU Rangaswamy, P Bourke, MAM Butt, DP AF Vaidya, RU Rangaswamy, P Bourke, MAM Butt, DP TI Measurement of bulk residual stresses in molybdenum disilicide stainless steel joints using neutron scattering SO ACTA MATERIALIA LA English DT Article ID CERAMIC ADHESIVE JOINTS; OXIDATION; THICKNESS; MOSI2 AB Neutron diffraction was used to measure the bulk residual strains in molybdenum disilicide (MoSi2)-316L stainless steel joints. The joints were produced by brazing disks of MoSi2 and 316L stainless steel along with an interlayer, using Cusil(TM) as the braze. This study explored the physical parameters of the interlayer on the average phase strains in the MoSi2 and 316L stainless steel. The effect of the coefficient of thermal expansion was explored by using three different interlayer materials; niobium, nickel, and nickel-iron. The residual strains in MoSi2 decreased significantly in both radial and axial directions with increasing niobium interlayer thickness. Residual strains were relatively insensitive to changes in the 500 mu m thick interlayer material. Finite element modeling results were corroborated by the neutron measurements on the joints allowing inferences to be drawn concerning the preference of the interlayer material. The results illustrate the importance of the ductile interlayer in the successful fabrication of MoSi2-316L stainless steel joints. (C) 1998 Acta Metallurgica Inc. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Vaidya, RU (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RI Butt, Darryl/B-7480-2008 OI Butt, Darryl/0000-0003-4501-8864 NR 18 TC 29 Z9 35 U1 1 U2 5 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2047 EP 2061 DI 10.1016/S1359-6454(97)00429-1 PG 15 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700019 ER PT J AU Luo, CP Dahmen, U AF Luo, CP Dahmen, U TI Interface structure of faceted lath-shaped Cr precipitates in a Cu-0.33 wt% Cr alloy SO ACTA MATERIALIA LA English DT Article ID FCC-BCC INTERFACES; O-LATTICE ANALYSES; INVARIANT LINE; BOUNDARIES; MORPHOLOGY; SYSTEMS; CU; CRYSTALLOGRAPHY; MARTENSITE; MISFIT AB The interface structure of lath-shaped, faceted Cr-rich precipitates in a Cu-0.33 wt%Cr alloy was investigated by transmission electron microscopy using diffraction contrast and weak beam dark field imaging techniques. The lath axis was aligned precisely with the [5 (6) over bar 1](f) invariant line direction, and its cross-sectional shape was characterized by four distinct facets with different defect contents. The major facet near (335)(f) appeared defect-free. The (111)(f) and (552)(f) facets showed a single set of ledges with a step height of similar to 1.1 nm and an associated displacement vector along similar to[335](f). The curved similar to(443)(f) side facets contained an array of dislocations spaced similar to 8.1 nm apart with a Burgers vector that could reasonably be characterized as 1/3[111](f) or 1/2[110](b), i.e. as d.s.c. lattice dislocations accommodating the misfit in interplanar spacing of the parallel close-packed planes in the two phases. A detailed model of the interface is in excellent agreement with the observed defect structure and the previously determined crystallographic characteristics. The model shows that the major facet near (335)(f) which appears to be defect free, actually contains a closely spaced array of dislocations in near-screw orientation. The uniform ledge height of similar to 1.1 nm in all interfaces is the plane spacing of the primary O-lattice planes of Zhang and Purdy. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. S China Univ Technol, Dept Mech Engn 2, Canton 510641, Peoples R China. RP Luo, CP (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Natl Ctr Electron Microscopy, Berkeley, CA 94720 USA. NR 38 TC 46 Z9 52 U1 1 U2 12 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2063 EP 2081 DI 10.1016/S1359-6454(97)00380-7 PG 19 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700020 ER PT J AU Hsueh, CH AF Hsueh, CH TI Some applications of two-dimensional stress transfer analyses SO ACTA MATERIALIA LA English DT Article ID FIBER PULL-OUT; CERAMIC COMPOSITES; MATRIX AB Two-dimensional stress transfer analyses are performed for the following system: a long central plate bonded on opposite sides along its length to two short plates and subjected to tensile loading at its ends. The load transfers from the long plate to the short plate through the interfacial shear stress. The system represents the unit cell of platelet-reinforced composites, in which parallel matrix cracks are uniformly spaced and are bridged by the platelet, in a two-dimensional sense. Analytical solutions for the crack opening displacement, the additional displacement of the composite due to the presence of cracks, and stress intensity factor at the crack tip are derived. Letting the long plate and the short plates have the same mechanical properties, the analytical solutions are compared to the existing numerical solutions for tensile loading of both a double edge notch strip and a semi-infinite plane with parallel edge cracks. Good agreement is obtained in this comparison. (C) 1998 Acta Metallurgica Inc. C1 Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Hsueh, CH (reprint author), Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RI Hsueh, Chun-Hway/G-1345-2011 NR 13 TC 2 Z9 2 U1 0 U2 1 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2131 EP 2138 DI 10.1016/S1359-6454(97)00426-6 PG 8 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700025 ER PT J AU Thomson, RC Miller, MK AF Thomson, RC Miller, MK TI Carbide precipitation in martensite during the early stages of tempering Cr- and Mo-containing low alloy steels SO ACTA MATERIALIA LA English DT Article ID FIELD-ION MICROSCOPY; ATOM-PROBE AB The microstructures of a 2.25% Cr-1% Mo-0.15 wt% C steel, and a steel with identical alloying additions but a higher carbon level, 2.25% Cr-1% Mo-0.4 wt% C, have been examined in the martensitic condition for a variety of tempering heat treatments by transmission electron microscopy and atom probe field ion microscopy. Ultra-thin films which were carbon enriched have been observed at some of the martensite lath boundaries. Brightly imaging clusters of Mo and C atoms, which represent the earliest stages of the precipitation of Mo2C carbide were observed. In the very early stages of ageing at 350 degrees C, individual molecular ions of MoN2+ were observed using atom probe selected area analysis. No partitioning of Cr, Mo and Mn, was observed between cementite and martensite after tempering at 350 degrees C for times up to 40 h. The enrichment behaviour and interface concentrations of Cr, Mn and Mo in the cementite after prolonged ageing at 450 degrees C for 187 h were found to be the same in both the low and high carbon alloys, despite the fact that the predicted equilibrium concentrations of the various alloying elements in the cementite were very different. These results demonstrate that cementite, in Cr and Mo containing alloy steels, precipitates from supersaturated ferrite via a paraequilibrium transformation mechanism. (C) 1998 Acta Metallurgica Inc. C1 Loughborough Univ Technol, Inst Polymer Technol & Mat Engn, Loughborough LE11 3TU, Leics, England. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. RP Thomson, RC (reprint author), Loughborough Univ Technol, Inst Polymer Technol & Mat Engn, Loughborough LE11 3TU, Leics, England. RI Thomson, Rachel/B-4217-2011 OI Thomson, Rachel/0000-0002-3681-0107 NR 28 TC 94 Z9 101 U1 1 U2 28 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2203 EP 2213 DI 10.1016/S1359-6454(97)00420-5 PG 11 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700031 ER PT J AU Schulthess, TC Turchi, PEA Gonis, A Nieh, TG AF Schulthess, TC Turchi, PEA Gonis, A Nieh, TG TI Systematic study of stacking fault energies of random Al-based alloys SO ACTA MATERIALIA LA English DT Article ID GRAIN-BOUNDARY; METALS; ALUMINUM AB We have determined intrinsic stacking fault energies, formation energies and structural energies differences for Al-X alloys, where X = Cu, Ag or Mg, from self-consistent electronic structure calculations, using the Layer Korringa Kohn Rostoker method within the coherent potential approximation. We find that the intrinsic stacking fault energy is almost equal to twice the energy difference between the h.c.p. and f.c.c. structures, which indicates that the inter-atomic interactions that are relevant for the structural properties are of short-range. A modified rigid band model is used to understand the origin of the non-linear variation of the stacking fault energy in Al-Cu and Al-Ag with composition. For the Al-Zn system we show that conclusions drawn from the rigid band model hold for any system in which Al is alloyed with an element that has a filled d-band. (C) 1998 Acta Metallurgica Inc. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Schulthess, TC (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Nieh, Tai-Gang/G-5912-2011 OI Nieh, Tai-Gang/0000-0002-2814-3746 NR 27 TC 58 Z9 60 U1 3 U2 22 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6454 J9 ACTA MATER JI Acta Mater. PD MAR 23 PY 1998 VL 46 IS 6 BP 2215 EP 2221 DI 10.1016/S1359-6454(97)00432-1 PG 7 WC Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Materials Science; Metallurgy & Metallurgical Engineering GA ZF480 UT WOS:000072901700032 ER PT J AU Omary, MA Webb, TR Assefa, Z Shankle, GE Patterson, HH AF Omary, MA Webb, TR Assefa, Z Shankle, GE Patterson, HH TI Crystal structure, electronic structure, and temperature-dependent Raman spectra of Tl[Ag(CN)(2)]: Evidence for ligand-unsupported argentophilic interactions SO INORGANIC CHEMISTRY LA English DT Review ID SOLID-STATE CLASS; POLYNUCLEAR GOLD(I) COMPLEXES; LANTHANIDE ION COMPLEXES; METAL-METAL INTERACTIONS; EXCHANGED ZEOLITE-A; EXCITED-STATE; PHOTOPHYSICAL PROPERTIES; SPECTROSCOPIC PROPERTIES; ENERGY-TRANSFER; PHOTOLUMINESCENCE PROPERTIES AB The structure of thallium dicyanoargentate(I) has been determined crystallographically. The crystal structure shows an Ag-Ag distance of 3.11 Angstrom. This is the shortest Ag-Ag distance reported for any silver dicyanide salt whose crystal structure has been determined. Raman spectra of the compound show four nu(C-N) peaks that are well-resolved in the 10-80 K temperature range. This result agrees well with group theory analysis. Extended Huckel calculations using relativistic wave functions have been carried out for two models which describe the interactions between the Ag(CN)(2)(-) ions within the crystal structure of Tl[Ag(CN)(2)]. The results of these calculations indicate the formation of potential wells at short Ag-Ag distances. The data in this study suggest the significance of ligand-unsupported silver-silver interactions (argentophilicity) in Tl[Ag(CN)(2)]. Tl-Ag interactions are determined to be insignificant in the compound. Tl[Ag(CN)(2)] crystallizes in the monoclinic space group P2(1)/c (No. 14), with a = 7.798(1) Angstrom, b = 14.685(3) Angstrom, c = 8.566(2) Angstrom, beta = 91.66(2)degrees, Z = 8, R = 0.0643, and R-w = 0.0899. C1 Univ Maine, Dept Chem, Orono, ME 04469 USA. Auburn Univ, Dept Chem, Auburn, AL 36849 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Angelo State Univ, San Angelo, TX 76909 USA. RP Patterson, HH (reprint author), Univ Maine, Dept Chem, Orono, ME 04469 USA. NR 110 TC 217 Z9 218 U1 3 U2 27 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 23 PY 1998 VL 37 IS 6 BP 1380 EP 1386 DI 10.1021/ic970694l PG 7 WC Chemistry, Inorganic & Nuclear SC Chemistry GA ZD901 UT WOS:000072735800034 ER PT J AU Hay, BP Yang, LR Lii, JH Allinger, NL AF Hay, BP Yang, LR Lii, JH Allinger, NL TI An extended MM3(96) force field for complexes of the group 1A and 2A cations with ligands bearing conjugated ether donor groups SO JOURNAL OF MOLECULAR STRUCTURE-THEOCHEM LA English DT Article DE calixarene; crown ether; metal complexes; molecular mechanics; spherand ID MOLECULAR MECHANICS; METAL-IONS; STRUCTURAL CRITERIA; SELECTIVE LIGANDS; RATIONAL DESIGN; CROWN-ETHERS; STABILITY; EXTENSION AB Structural requirements for strain-free metal ion complexation by a conjugated ether group are investigated through the use of both electronic structure calculations and molecular mechanics calculations. Hartree-Fock calculations on simple model complexes, [M(anisole)](n+) and [M(1,2-dimethoxybenzene)](n+), reveal a preference for trigonal planar oxygen geometry when conjugated ether oxygens are coordinated to alkali and alkaline earth cations. Potential energy surfaces from the Hartree-Fock calculations are used, in part, to develop MM3(96) force field parameters for calculation on complexes of ligands bearing conjugated ether donor atoms with the alkali (Li to Cs) and alkaline earth (Mg to Ba) cations. The extended MM3(96) model reproduces the experimental crystal structures of 42 complexes of multidentate ether ligands with the alkali and alkaline earth cations. A novel feature of the MM3(96) program is reported which facilitates the treatment of metal-centered bond angles in complexes where there are greater than six donor atoms. (C) 1998 Elsevier Science B.V. C1 Pacific NW Lab, Richland, WA 99352 USA. Univ Georgia, Dept Chem, Computat Ctr Mol Struct & Design, Athens, GA 30602 USA. RP Pacific NW Lab, POB 999,Mailstop K1-83, Richland, WA 99352 USA. NR 20 TC 20 Z9 20 U1 0 U2 5 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0166-1280 J9 J MOL STRUC-THEOCHEM JI Theochem-J. Mol. Struct. PD MAR 23 PY 1998 VL 428 BP 203 EP 219 DI 10.1016/S0166-1280(97)00280-7 PG 17 WC Chemistry, Physical SC Chemistry GA ZE979 UT WOS:000072850700022 ER PT J AU Raymond, S Regnault, LP Kambe, S Flouquet, J Lejay, P AF Raymond, S Regnault, LP Kambe, S Flouquet, J Lejay, P TI Switching of the magnetic interactions from antiferromagnetic to ferromagnetic in the heavy-fermion compound CeRu2Si2 under high magnetic field SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID INELASTIC NEUTRON-SCATTERING; METAMAGNETIC TRANSITION; SPIN FLUCTUATIONS; SYSTEMS; INSTABILITY; ITINERANT AB Inelastic neutron scattering studies of CeRu2Si2 under high magnetic field are reported. The dynamic short-range antiferromagnetic correlations are progressively replaced by static long-range ferromagnetic order when the field is increased. A simple interpretation using a phenomenological model leads to the conclusion I:hat the exchange interactions are field dependent and that their weight is shifted from the antiferromagnetic point to the ferromagnetic point as the field changes. C1 CEA Grenoble, Dept Rech Fondamentale Mat Condensee, MDN, SPSMS, F-38054 Grenoble 9, France. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. CNRS, Ctr Rech Tres Basses Temp, F-38042 Grenoble 9, France. RP Raymond, S (reprint author), CEA Grenoble, Dept Rech Fondamentale Mat Condensee, MDN, SPSMS, F-38054 Grenoble 9, France. NR 30 TC 22 Z9 22 U1 1 U2 2 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAR 23 PY 1998 VL 10 IS 11 BP 2363 EP 2373 DI 10.1088/0953-8984/10/11/002 PG 11 WC Physics, Condensed Matter SC Physics GA ZF965 UT WOS:000072951000002 ER PT J AU Palles, D Liarokapis, E Leventouri, T Chakoumakos, BC AF Palles, D Liarokapis, E Leventouri, T Chakoumakos, BC TI The effect of Ca substitution on the structure and the Raman active phonons in Y1-xCaxBa2Cu3O7-delta SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Article ID RARE-EARTH; SUPERCONDUCTIVITY; MODES AB Micro-Raman measurements and Rietveld refinements of x-ray data have been carried out in the superconducting system Y1-xCaxBa2Cu3O7-delta with 0 less than or equal to x less than or equal to 0.12, to delineate the effect of the excess doping on the Raman active phonons and especially on the characteristics of the plane oxygen modes. The increase of the Cu(2)-O(4) bond length with increasing Ca concentration induces a much smaller decrease in the frequency of the A(g) phonon of the apical 0(4) atom than the rare earth substitutions for Y. The frequency of the in-phase A(g) vibrations of the plane oxygens decreases slightly with increasing Ca content, but remains well above the lowest value that has been reported for the oxygen overdoped pure YBa2Cu3O7-delta compound, suggesting that the softening of this mode observed in those samples may not be attributed to the addition of carriers. The frequency of the out-of-phase B-1g-like vibrations of the plane oxygens is not affected by the substitution, but the width of the corresponding phonon increases considerably. This increase is due to the appearance of another mode of B-1g symmetry that could correspond to a hypothetical CaBa2Cu3O7-delta phase separated from the pure YBCO phase. C1 Natl Tech Univ Athens, Dept Phys, Athens 15780, Greece. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Palles, D (reprint author), Natl Tech Univ Athens, Dept Phys, Athens 15780, Greece. RI Palles, Dimitrios/L-8218-2013; Chakoumakos, Bryan/A-5601-2016 OI Chakoumakos, Bryan/0000-0002-7870-6543 NR 16 TC 10 Z9 10 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAR 23 PY 1998 VL 10 IS 11 BP 2515 EP 2524 DI 10.1088/0953-8984/10/11/015 PG 10 WC Physics, Condensed Matter SC Physics GA ZF965 UT WOS:000072951000015 ER PT J AU Chanowitz, MS AF Chanowitz, MS TI Combining real and virtual Higgs boson mass constraints SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTROWEAK AB Within the framework of the standard model we observe that there is a significant discrepancy between the most precise Z boson decay asymmetry measurement and the limit from direct searches for Higgs boson production. Using methods inspired by the Particle Data Group we explore the possible effect on fits of the Higgs boson mass. In each case the central value and the 95% confidence level upper limit increase significantly relative to the conventional fit. The results suggest caution in drawing conclusions about the Higgs boson mass from the existing data. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. RP Chanowitz, MS (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Theoret Phys Grp, Berkeley, CA 94720 USA. NR 8 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2521 EP 2524 DI 10.1103/PhysRevLett.80.2521 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200006 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Coxe, RL Crane, D Cronin-Hennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, G Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fukui, Y Funaki, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Happacher, F Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Kostka, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, UC Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R Mazzanti, P McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tannenbaum, B Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Asakawa, T Ashmanskas, W Atac, M Azfar, F Azzi-Bacchetta, P Bacchetta, N Badgett, W Bagdasarov, S Bailey, MW Bao, J de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Barzi, E Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Benlloch, J Bensinger, J Benton, D Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Binkley, M Bisello, D Blair, RE Blocker, C Bodek, A Bokhari, W Bolognesi, V Bolla, G Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Cammerata, J Campagnari, C Campbell, M Caner, A Carithers, W Carlsmith, D Castro, A Cauz, D Cen, Y Cervelli, F Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chikamatsu, T Chiou, CN Christofek, L Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Couyoumtzelis, C Coxe, RL Crane, D Cronin-Hennessy, D Culbertson, R Daniels, T DeJongh, F Delchamps, S Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Dunn, A Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, G Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Frautschi, M Freeman, J Friedman, J Frisch, H Fukui, Y Funaki, S Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gladney, L Glenzinski, D Gold, M Gonzalez, J Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handler, R Hans, RM Happacher, F Hara, K Hardman, AD Harral, B Harris, RM Hauger, SA Hauser, J Hawk, C Hayashi, E Heinrich, J Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C Hollebeek, R Holloway, L Hong, S Houk, G Hu, P Huffman, BT Hughes, R Huston, J Huth, J Hylen, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y Jensen, H Joshi, U Kadel, RW Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kesten, P Kestenbaum, D Keutelian, H Keyvan, F Kharadia, B Kim, BJ Kim, DH Kim, HS Kim, SB Kim, SH Kim, YK Kirsch, L Koehn, P Kondo, K Konigsberg, J Kopp, S Kordas, K Korytov, A Kostka, W Kovacs, E Kowald, W Krasberg, M Kroll, J Kruse, M Kuwabara, T Kuhlmann, SE Kuns, E Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, UC Lockyer, N Long, O Loomis, C Loreti, M Lu, J Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maghakian, A Maksimovic, P Mangano, M Mansour, J Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mattingly, R Mazzanti, P McIntyre, P Melese, P Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Mitsushio, H Miyamoto, T Miyashita, S Moggi, N Morita, Y Mukherjee, A Muller, T Murat, P Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Ninomiya, M Nodulman, L Oh, SH Ohl, KE Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Oliveira, R Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Park, S Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Romano, J Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Sganos, G Shapiro, MD Shaw, NM Shen, Q Shepard, PF Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Skarha, J Sliwa, K Snider, FD Song, T Spalding, J Speer, T Sphicas, P Spinella, F Spiropulu, M Spiegel, L Stanco, L Steele, J Stefanini, A Strahl, K Strait, J Strohmer, R Stuart, D Sullivan, G Sumorok, K Suzuki, J Takada, T Takahashi, T Takano, T Takikawa, K Tamura, N Tannenbaum, B Tartarelli, F Taylor, W Teng, PK Teramoto, Y Tether, S Theriot, D Thomas, TL Thun, R Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Uemura, N Ukegawa, F Unal, G Valls, J van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vondracek, M Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, J Wang, MJ Wang, QF Warburton, A Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Ye, Y Yeh, GP Yeh, P Yin, M Yoh, J Yosef, C Yoshida, T Yovanovitch, D Yu, I Yu, L Yun, JC Zanetti, A Zetti, F Zhang, L Zhang, W Zucchelli, S CA CDF Collaboration TI Search for flavor-changing neutral current decays of the top quark in p(p)over-bar collisions at root s = 1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID SILICON VERTEX DETECTOR; (P)OVER-BAR-P COLLISIONS; COLLIDER DETECTOR; PBARP COLLISIONS; Z-BOSONS; FERMILAB AB We search for the flavor-changing neutral current decays of the top quark t --> q gamma and t --> qZ (here q represents the c and u quarks) in (p) over bar p collisions at root s = 1.8 TeV. We use a dataset (integral L dt similar to 110 pb(-1)) collected during the 1992-1995 run of the Collider Detector at Fermilab. We set 95% confidence level limits on the branching fractions B(t --> q gamma) < 3.2% and B(t --> qZ) < 33%, consistent with the standard model. C1 KEK, Natl Lab High Energy Phys, Tsukuba, Ibaraki 315, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02264 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 28708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 33611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87132 USA. Ohio State Univ, Columbus, OH 43320 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Ist Nazl Fis Nucl, I-36132 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15270 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14628 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08854 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53806 USA. Yale Univ, New Haven, CT 06511 USA. RP Abe, F (reprint author), KEK, Natl Lab High Energy Phys, Tsukuba, Ibaraki 315, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Kim, Soo-Bong/B-7061-2014; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015; vilar, rocio/D-7454-2014 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580; NR 16 TC 120 Z9 120 U1 0 U2 6 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2525 EP 2530 DI 10.1103/PhysRevLett.80.2525 PG 6 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200007 ER PT J AU Czarnecki, A Melnikov, K AF Czarnecki, A Melnikov, K TI Two-loop QCD corrections to the heavy quark pair production cross section in e(+)e(-) annihilation near threshold SO PHYSICAL REVIEW LETTERS LA English DT Article ID MINIMAL SUBTRACTION SCHEME; OPERATOR EXPANSIONS AB We present O(alpha(s)(2)) corrections to the cross section for e(+)e(-) --> gamma* --> Q (Q) over bar close to threshold. We assume that the energy of the reaction is such that both the perturbative expansion in the strong coupling constant ct, and expansion in the velocity beta of the heavy quarks can be used. We obtain terms O(alpha(s)(2)/beta(2), alpha(s)(2)/beta, alpha(s)(2)) in the relative correction. We demonstrate how an expansion of Feynman diagrams in the threshold region is constructed. We obtain a matching relation between the vector current in full QCD and in nonrelativistic QCD. C1 Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. Univ Karlsruhe, Inst Theoret Teilchenphys, D-76128 Karlsruhe, Germany. RP Czarnecki, A (reprint author), Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. NR 17 TC 135 Z9 135 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2531 EP 2534 DI 10.1103/PhysRevLett.80.2531 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200008 ER PT J AU van Leeuwe, JJ Blok, HP van den Brand, JFJ Bulten, HJ Dodge, GE Ent, R Hesselink, WHA Jans, E Kasdorp, WJ Laget, JM Lapikas, L Nagorny, SI Onderwater, CJG Pellegrino, AR Spaltro, CM Steijger, JJM Schiavilla, R Templon, JA Unal, O AF van Leeuwe, JJ Blok, HP van den Brand, JFJ Bulten, HJ Dodge, GE Ent, R Hesselink, WHA Jans, E Kasdorp, WJ Laget, JM Lapikas, L Nagorny, SI Onderwater, CJG Pellegrino, AR Spaltro, CM Steijger, JJM Schiavilla, R Templon, JA Unal, O TI High-missing-momentum components in the He-4(e,e ' p)H-3 reaction SO PHYSICAL REVIEW LETTERS LA English DT Article ID FEW-BODY SYSTEMS; ELECTRON-SCATTERING; HE-4; ELECTRODISINTEGRATION; NUCLEI AB The cross section of the He-4(e, e'p)H-3 reaction has been measured for missing momenta 220 less than or equal to p(m) less than or equal to 690 MeV/c to study high-momentum components of the nuclear wave function and the reaction mechanism for this transition. The zero predicted in the plane-wave impulse approximation (PWIA) cross section, due to the underlying pt momentum distribution, is found to be washed out. Three types of calculations indicate that this is caused by final-state interactions and contributions from two-body currents. The calculations reproduce the high p(m) (600-690 MeV/c) data, although due to different ingredients in the models. C1 NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Vrije Univ Amsterdam, NL-1081 HV Amsterdam, Netherlands. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. TJNAF, Newport News, VA 23606 USA. Old Dominion Univ, Norfolk, VA 23529 USA. CEA Saclay, Serv Phys Nucl, F-91191 Gif Sur Yvette, France. RP Jans, E (reprint author), NIKHEF H, POB 41882, NL-1009 DB Amsterdam, Netherlands. OI Templon, Jeffrey/0000-0002-3371-788X NR 26 TC 14 Z9 14 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2543 EP 2546 DI 10.1103/PhysRevLett.80.2543 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200011 ER PT J AU Ahmad, I Bonino, G Castagnoli, GC Fischer, SM Kutschera, W Paul, M AF Ahmad, I Bonino, G Castagnoli, GC Fischer, SM Kutschera, W Paul, M TI Three-laboratory measurement of the Ti-44 half-life SO PHYSICAL REVIEW LETTERS LA English DT Article AB We report on a measurement of the Ti-44 half-life aimed at lowering existing systematic uncertainties in this value, which is important to astrophysics. The half-life was measured by following the decay of Ti-44 relative to Co-60 for about 5 yr and the measurements were performed independently in three laboratories - Argonne, Jerusalem, and Torino. We suggest to combine our result, 59.0 +/- 0.6 yr, with the one from the accompanying Letter by Gorres et al., 50.3 +/- 1.3 yr, to obtain a current "best value" for the half-life of Ti-44 of 59.2 +/- 0.6 yr (1 sigma error). C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. CNR, Ist Cosmogeofis, I-10133 Turin, Italy. Univ Turin, Dipartimento Fis Gen, I-10125 Turin, Italy. Univ Vienna, Inst Radiumforsch & Kernphys, A-1090 Vienna, Austria. Hebrew Univ Jerusalem, Racah Inst Phys, IL-91904 Jerusalem, Israel. RP Ahmad, I (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 15 TC 59 Z9 60 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2550 EP 2553 DI 10.1103/PhysRevLett.80.2550 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200013 ER PT J AU Svensson, CE Baktash, C Ball, GC Cameron, JA Devlin, M Eberth, J Flibotte, S Galindo-Uribarri, A Haslip, DS Janzen, VP LaFosse, DR Lee, IY Macchiavelli, AO MacLeod, RW Nieminen, JM Paul, SD Radford, DC Riedinger, LL Rudolph, D Sarantites, DG Thomas, HG Waddington, JC Ward, D Weintraub, W Wilson, JN Afanasjev, AV Ragnarsson, I AF Svensson, CE Baktash, C Ball, GC Cameron, JA Devlin, M Eberth, J Flibotte, S Galindo-Uribarri, A Haslip, DS Janzen, VP LaFosse, DR Lee, IY Macchiavelli, AO MacLeod, RW Nieminen, JM Paul, SD Radford, DC Riedinger, LL Rudolph, D Sarantites, DG Thomas, HG Waddington, JC Ward, D Weintraub, W Wilson, JN Afanasjev, AV Ragnarsson, I TI Smooth termination of rotational bands in Zn-62: Evidence for a loss of collectivity SO PHYSICAL REVIEW LETTERS LA English DT Article ID MASS REGION; NUCLEI AB Two sets of strongly coupled rotational bands have been identified in Zn-62. These bands have been observed up to the terminating states of their respective configurations. Lifetime measurements indicate that the transition quadrupole moments in these bands decrease as termination is approached. These results establish the first terminating states of rotational bands in the A similar to 60 mass region and confirm the predicted loss of collectivity associated with smooth band termination. C1 McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. Oak Ridge Natl Lab, Div Phys, Oak Ridge, TN 37831 USA. Atom Energy Canada Ltd, Chalk River Labs, Chalk River, ON K0J 1J0, Canada. Washington Univ, Dept Chem, St Louis, MO 63130 USA. Univ Cologne, Inst Kernphys, D-50937 Cologne, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Nucl Sci, Berkeley, CA 94720 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Univ Munich, Sekt Phys, D-85748 Garching, Germany. Lund Inst Technol, Dept Math Phys, S-22100 Lund, Sweden. Latvian Acad Sci, Nucl Res Ctr, LV-2169 Salaspils, Latvia. RP Svensson, CE (reprint author), McMaster Univ, Dept Phys & Astron, Hamilton, ON L8S 4M1, Canada. RI Rudolph, Dirk/D-4259-2009; Devlin, Matthew/B-5089-2013; radford, David/A-3928-2015 OI Rudolph, Dirk/0000-0003-1199-3055; Devlin, Matthew/0000-0002-6948-2154; NR 25 TC 70 Z9 71 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2558 EP 2561 DI 10.1103/PhysRevLett.80.2558 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200015 ER PT J AU Kramer, GJ Saigusa, M Ozeki, T Kusama, Y Kimura, H Oikawa, T Tobita, K Fu, GY Cheng, CZ AF Kramer, GJ Saigusa, M Ozeki, T Kusama, Y Kimura, H Oikawa, T Tobita, K Fu, GY Cheng, CZ TI Noncircular triangularity and ellipticity-induced Alfven eigenmodes observed in JT-60U SO PHYSICAL REVIEW LETTERS LA English DT Article ID FUSION ALPHA-PARTICLES; TOROIDAL PLASMAS; TAE MODES; DIII-D; INSTABILITIES; STABILITY; TOKAMAK; EXCITATION; IONS; JET AB For the first time noncircular triangularity induced Alfven eigenmodes (NAE) were observed in combined ion cyclotron resonance frequency and neutral beam injection heated plasmas. Ellipticity induced Alfven eigenmodes (EAE) and toroidicity-induced Alfven eigenmodes (TAE) were also observed in those plasmas. The threshold beta of the energetic ions for exciting the NAE modes was found to be similar to that for exciting TAE modes. C1 Japan Atom Energy Res Inst, Naka Fus Res Estab, Ibaraki, Osaka, Japan. Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Kramer, GJ (reprint author), Japan Atom Energy Res Inst, Naka Fus Res Estab, Ibaraki, Osaka, Japan. RI Cheng, Chio/K-1005-2014 NR 22 TC 31 Z9 32 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2594 EP 2597 DI 10.1103/PhysRevLett.80.2594 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200024 ER PT J AU Shvets, G Fisch, NJ Rax, JM AF Shvets, G Fisch, NJ Rax, JM TI Tunable radiation source through upshifting without ionization SO PHYSICAL REVIEW LETTERS LA English DT Article ID CAPACITOR ARRAY; SPECTRAL-LINES; GENERATION; ACCELERATOR; SCATTERING; SHIFTS; PULSES; PLASMA; FRONT; RAMAN AB A mechanism for generating electromagnetic wakes of infrared radiation by a short laser pulse, propagating through an underdense plasma in the presence of a magnetostatic undulator, is described. As opposed to the undulator radiation, produced when a charged particle bunch propagates in a periodic magnetic field, here a laser pulse is used instead of the particle bunch. This mechanism for a tunable, plasma-based radiation source does not rely on ionization or photoswitching. It is also found that, in the presence of a static periodic magnetic field, long laser pulses become modulationally unstable, generating an electromagnetic wake. C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. Univ Paris 11, Phys Gaz & Plasmas Lab, F-91405 Orsay, France. RP Shvets, G (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 18 TC 8 Z9 8 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2598 EP 2601 DI 10.1103/PhysRevLett.80.2598 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200025 ER PT J AU Wei, J Okamoto, H Sessler, AM AF Wei, J Okamoto, H Sessler, AM TI Necessary conditions for attaining a crystalline beam SO PHYSICAL REVIEW LETTERS LA English DT Article ID STORED ION-BEAM; CAVITY AB Molecular dynamics is employed to study the nature and magnitude of beam cooling that is required in order to achieve a crystalline beam. Analysis is presented of a number of cooling systems now in use, or whose use is contemplated, none of which has been shown to be able to achieve the crystalline state. However, for an adequately strong cooling system that produces on average a constant angular velocity among the particles, a crystalline state can be achieved. In this paper, we present numerical values for a particular example under typical experimental conditions; these values appear to be achievable in practice. C1 Brookhaven Natl Lab, Upton, NY 11973 USA. Kyoto Univ, Inst Chem Res, Accelerator Lab, Kyoto 611, Japan. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Wei, J (reprint author), Brookhaven Natl Lab, Upton, NY 11973 USA. NR 16 TC 68 Z9 69 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2606 EP 2609 DI 10.1103/PhysRevLett.80.2606 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200027 ER PT J AU Aranson, IS Chate, H Tang, LH AF Aranson, IS Chate, H Tang, LH TI Spiral motion in a noisy complex Ginzburg-Landau equation SO PHYSICAL REVIEW LETTERS LA English DT Article ID BOSE-EINSTEIN CONDENSATION; WAVES; TURBULENCE; MEDIA AB The response of spiral waves to external perturbations in a stable regime of the two-dimensional complex Ginzburg-Landau equation (CGLE) is investigated. It is shown that the spiral core has a finite mobility and performs Brownian motion when driven by white noise. Combined with simulation results, this suggests that defect-free and quasifrozen states in the noiseless CGLE are susceptible to unpaired vortex excitation at any nonzero noise strength. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. CENS, CEA, Serv Phys Etat Condense, F-91191 Gif Sur Yvette, France. Hong Kong Baptist Univ, Dept Phys, Hong Kong, Hong Kong. Hong Kong Baptist Univ, Ctr Nonlinear & Complex Syst, Hong Kong, Hong Kong. RP Aranson, IS (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Aranson, Igor/I-4060-2013; Chate, Hugues/D-2156-2015 OI Chate, Hugues/0000-0002-6098-4094 NR 17 TC 21 Z9 21 U1 0 U2 4 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2646 EP 2649 DI 10.1103/PhysRevLett.80.2646 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200037 ER PT J AU Sow, CH Harada, K Tonomura, A Crabtree, G Grier, DG AF Sow, CH Harada, K Tonomura, A Crabtree, G Grier, DG TI Measurement of the vortex pair interaction potential in a type-II superconductor SO PHYSICAL REVIEW LETTERS LA English DT Article ID MICROSCOPY; COEXISTENCE; LATTICES; VORTICES AB We describe the first direct measurement of the pair interaction potential for magnetic flux lines in a type-II superconductor. Our approach relies on a quantitative analysis of Lorentz microscope images of vortices creeping through a superconducting thin film. Time-resolved vortex distributions imaged in this way reflect both the vortices' mutual interaction and also the influence of random pinning forces. These influences are isolated and quantified by adapting results from the theory of simple liquids. C1 Univ Chicago, James Franck Inst, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Hitachi Ltd, Adv Res Lab, Hatoyama, Saitama 35003, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. RP Sow, CH (reprint author), Univ Chicago, James Franck Inst, 5640 S Ellis Ave, Chicago, IL 60637 USA. RI Grier, David/C-5761-2008; Sow, Chorng Haur/G-1685-2012 OI Grier, David/0000-0002-4382-5139; NR 19 TC 27 Z9 27 U1 3 U2 7 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 23 PY 1998 VL 80 IS 12 BP 2693 EP 2696 DI 10.1103/PhysRevLett.80.2693 PG 4 WC Physics, Multidisciplinary SC Physics GA ZD178 UT WOS:000072659200049 ER PT J AU Meyrath, TP James, DFV AF Meyrath, TP James, DFV TI Theoretical and numerical studies of the positions of cold trapped ions SO PHYSICS LETTERS A LA English DT Article DE ion traps; numerical simulations; experimental quantum computing ID PHASE-TRANSITIONS; QUANTUM AB We examine the properties of cold ions confined by a Paul trap in a linear crystal configuration, a system of considerable current interest due to its application to practical quantum computation. Using a combination of theoretical and numerical calculations, a semi-empirical formula for the positions of the ions is derived. (C) 1998 Published by Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Div Theoret T4, Los Alamos, NM 87545 USA. Georgia Inst Technol, Atlanta, GA 30332 USA. Univ Calif Los Alamos Natl Lab, Los Alamos Summer Sch AMO Phys, Los Alamos, NM 87544 USA. Univ New Mexico, Los Alamos, NM 87544 USA. RP James, DFV (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret T4, Mailstop B-268, Los Alamos, NM 87545 USA. RI James, Daniel/B-9805-2009 OI James, Daniel/0000-0003-3981-4602 NR 15 TC 11 Z9 11 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 23 PY 1998 VL 240 IS 1-2 BP 37 EP 42 DI 10.1016/S0375-9601(98)00045-0 PG 6 WC Physics, Multidisciplinary SC Physics GA ZJ106 UT WOS:000073180100006 ER PT J AU Diez, E Gomez-Alcala, R Dominguez-Adame, F Sanchez, A Berman, GP AF Diez, E Gomez-Alcala, R Dominguez-Adame, F Sanchez, A Berman, GP TI Coherent carrier dynamics in semiconductor superlattices SO PHYSICS LETTERS A LA English DT Article ID RABI OSCILLATIONS AB We investigate the coherent dynamics of carriers in semiconductor superlattices driven by ac-dc electric fields. We solve numerically the time-dependent effective-mass equation for the envelope function. We find that carriers undergo Rabi oscillations when the driving frequency is close to the separation between minibands. (C) 1998 Elsevier Science B.V. C1 Univ Carlos III Madrid, GISC, Dept Matemat, E-28911 Madrid, Spain. Univ Vigo, Dept Tecnol Comunicac, E-36200 Vigo, Spain. Univ Complutense Madrid, GISC, Dept Fis Mat, E-28040 Madrid, Spain. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, CNLS, Los Alamos, NM 87545 USA. LV Kirensky Phys Inst, Krasnoyarsk 660036, Russia. RP Diez, E (reprint author), Univ Carlos III Madrid, GISC, Dept Matemat, E-28911 Madrid, Spain. RI Sanchez, Angel/A-9229-2008; Dominguez-Adame, Francisco/E-4277-2010; ENRIQUE, DIEZ/M-3691-2014; OI Sanchez, Angel/0000-0003-1874-2881; Dominguez-Adame, Francisco/0000-0002-5256-4196; ENRIQUE, DIEZ/0000-0001-7964-4148; Gomez Alcala, Rafael/0000-0002-6472-8987 NR 7 TC 14 Z9 15 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 23 PY 1998 VL 240 IS 1-2 BP 109 EP 111 DI 10.1016/S0375-9601(98)00023-1 PG 3 WC Physics, Multidisciplinary SC Physics GA ZJ106 UT WOS:000073180100020 ER PT J AU Narayan, RL King, TS AF Narayan, RL King, TS TI Hydrogen adsorption states on silica-supported Ru-Ag and Ru-Cu bimetallic catalysts investigated via microcalorimetry SO THERMOCHIMICA ACTA LA English DT Article DE Ru bimetallic catalysts; hydrogen adsorption; microcalorimetry ID CARBON-MONOXIDE HYDROGENATION; NUCLEAR-MAGNETIC-RESONANCE; ADSORBED HYDROGEN; COPPER CATALYSTS; RUTHENIUM; CHEMISORPTION; SURFACES; CO; MECHANISM; RU/SIO2 AB The nature of hydrogen adsorption states on silica supported Ru, Ru-Ag and Ru-Cu was investigated using microcalorimetry and selective hydrogen chemisorption. The differential heats of hydrogen adsorption as a function of hydrogen coverage were determined for Ru and bimetallics with varying Ag and Cu contents. The initial heats of hydrogen adsorption (differential heat at coverages approaching zero) were found to be similar on all three catalyst systems suggesting the absence of effects that directly alter the chemisorptive bond (e.g. electron transfer between Ru and the added metal). The addition Ag to Ru significantly reduced the total amount of hydrogen adsorbed per surface Ru atom. That is, the stoichiometry of adsorption was altered by the addition of Ag even though Ag does not adsorb hydrogen. Similarly, the addition of Cu reduced the amount of hydrogen adsorbed per surface metal atom. In both cases, the reduced amount of hydrogen adsorbed per surface atom (adsorptive stoichiometry) was associated with the loss of hydrogen adsorbed from weak and intermediate energy adsorption states (<80 kJ/mol). The population of sites with adsorption energies greater than or equal to 80 kJ/mol were unaffected. From atomistic simulations it is known that, at low concentrations, Ag and Cu preferentially occupy the low coordination metal sites. The loss of the intermediate and low adsorption energy sites is correlated with replacement of Ru atoms at edge, corner and other defectlike sites by Ag and Cu. Possible reasons for this structure sensitivity are discussed. (C) 1998 Elsevier Science B.V. C1 Iowa State Univ, Dept Chem Engn, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RP King, TS (reprint author), Kansas State Univ, 146 Rathbone Hall, Manhattan, KS 66506 USA. NR 54 TC 24 Z9 24 U1 2 U2 13 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-6031 J9 THERMOCHIM ACTA JI Thermochim. Acta PD MAR 23 PY 1998 VL 312 IS 1-2 BP 105 EP 114 DI 10.1016/S0040-6031(97)00444-9 PG 10 WC Thermodynamics; Chemistry, Analytical; Chemistry, Physical SC Thermodynamics; Chemistry GA ZD975 UT WOS:000072744500011 ER PT J AU Hsu, CW Evans, M Stimson, S Ng, CY AF Hsu, CW Evans, M Stimson, S Ng, CY TI Rotationally resolved photoelectron study of O-2: Identification of the vibrational progressions for O-2(+)(2(2)Pi(u),(2)Sigma(-)(u)) at 19.6-21.0 eV SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CONFIGURATION-INTERACTION CALCULATIONS; RESOLUTION THRESHOLD PHOTOELECTRON; DIATOMIC-MOLECULES; PHOTOIONIZATION; SPECTROSCOPY; OXYGEN; SPECTRUM; STATES AB On the basis of rotationally resolved pulsed field ionization photoelectron measurements, we have shown that the weak vibrational progressions in the energy region of 19.6-21.0 eV observed in recent high resolution photoelectron spectroscopic studies of O-2 are associated with transitions to the 2 (2) Pi(u 1/2) (2 (2) Pi(u 3/2)) and 2 Sigma(u)(-)states of O-2(+), with ionization energies of 19.6268+/-0.0005 eV (19.6329+/-0.0005 eV) and 20.3528+/-0.0005 eV, respectively. (C) 1998 American Institute of Physics. C1 US DOE, Ames Lab, Ames, IA 50011 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. Iowa State Univ Sci & Technol, Dept Chem, Ames, IA 50011 USA. RP Ng, CY (reprint author), US DOE, Ames Lab, Ames, IA 50011 USA. NR 24 TC 14 Z9 16 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 1998 VL 108 IS 12 BP 4701 EP 4704 DI 10.1063/1.475920 PG 4 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZC518 UT WOS:000072588400003 ER PT J AU Dunning, TH Peterson, KA AF Dunning, TH Peterson, KA TI Use of Moller-Plesset perturbation theory in molecular calculations: Spectroscopic constants of first row diatomic molecules SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID GAUSSIAN-BASIS SETS; CONFIGURATION-INTERACTION CALCULATIONS; WAVE-FUNCTIONS; BENCHMARK CALCULATIONS; CONVERGENCE; SERIES; ENERGIES; NEON; FREQUENCIES; HYDRIDES AB The convergence of Moller-Plesset perturbation expansions (MP2-MP4/MP5) for the spectroscopic constants of a selected set of diatomic molecules (BH, CH, HF, N-2, CO, and F-2) has been investigated. It was found that the second-order perturbation contributions to the spectroscopic constants are strongly dependent on basis set, more so for HF and CO than for BH. The MP5 contributions for HF were essentially zero for the cc-pVDZ basis set, but increased significantly with basis set illustrating the difficulty of using small basis sets as benchmarks for correlated calculations. The convergence behavior of the exact Moller-Plesset perturbation expansions were investigated using estimates of the complete basis set limits obtained using large correlation consistent basis sets. For BH and CH, the perturbation expansions of the spectroscopic constants converge monotonically toward the experimental values, while for HF, N-2, CO, and F-2, the expansions oscillate about the experimental values. The perturbation expansions are, in general, only slowly converging and, for HF, N-2, CO, and F-2, appear to be far from convergence at MP4. In fact, for HF, N-2, and CO, the errors in the calculated spectroscopic constants for the MP4 method are larger than those for the MP2 method (the only exception is D-e). The current study, combined with other recent studies, raises serious doubts about the use of Moller-Plesset perturbation theory to describe electron correlation effects in atomic and molecular calculations. (C) 1998 American Institute of Physics. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Washington State Univ, Dept Chem, Richland, WA 99352 USA. RP Pacific NW Lab, Environm Mol Sci Lab, POB 999, Richland, WA 99352 USA. NR 36 TC 45 Z9 45 U1 1 U2 5 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 1998 VL 108 IS 12 BP 4761 EP 4771 DI 10.1063/1.476308 PG 11 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZC518 UT WOS:000072588400010 ER PT J AU Simpson, WC Orlando, TM Parenteau, L Nagesha, K Sanche, L AF Simpson, WC Orlando, TM Parenteau, L Nagesha, K Sanche, L TI Dissociative electron attachment in nanoscale ice films: Thickness and charge trapping effects SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID CORE-EXCITED RESONANCES; STIMULATED DESORPTION; MOLECULAR-SOLIDS; PHYSISORBED O-2; AMORPHOUS WATER; THIN-FILMS; ENERGY; H2O; SURFACES; DEPENDENCE AB The yield and kinetic energy (KE) distributions of D- ions produced via dissociative electron attachment (DEA) resonances in nanoscale D2O ice films are collected as a function of film thickness. The B-2(1), (2)A(1), and B-2(2) DEA resonances shift to higher energies and their D- ion yields first increase and then decrease as the D2O films thicken. The D- KE distributions also shift to higher energy with increasing film thickness. We interpret the changes in the DEA yield and the D- KE distributions in terms of modifications in the electronic and geometric structure of the surface of the film as it thickens. A small amount of charge build-up occurs following prolonged electron beam exposure at certain energies, which primarily affects the D- KE distributions. Charge trapping measurements indicate that an enhancement in the trapping cross section occurs at energies near zero and between 6 and 10 eV. (C) 1998 American Institute of Physics. C1 Pacific NW Lab, WR Wiley Environm Mol Sci Lab, Richland, WA 99352 USA. Univ Sherbrooke, Fac Med, Canadian Med Res Grp Radiat Sci, Sherbrooke, PQ J1K 5N4, Canada. RP Orlando, TM (reprint author), Pacific NW Lab, WR Wiley Environm Mol Sci Lab, POB 999,M-S K8-88, Richland, WA 99352 USA. NR 50 TC 67 Z9 67 U1 1 U2 5 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 22 PY 1998 VL 108 IS 12 BP 5027 EP 5034 DI 10.1063/1.475924 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZC518 UT WOS:000072588400036 ER PT J AU Koska, W Delchamps, SW Kinney, W Lewis, DC Limon, PJ Ronzhin, A Strait, J Fiori, I Gallinaro, M Pischalnikov, Y Shen, Q AF Koska, W Delchamps, SW Kinney, W Lewis, DC Limon, PJ Ronzhin, A Strait, J Fiori, I Gallinaro, M Pischalnikov, Y Shen, Q TI Evaluation of candidate photomultiplier tubes for the upgrade of the CDF end plug calorimeter SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article DE phototubes; calorimeter; detector; high energy physics AB The Collider Detector at Fermilab is upgrading its end plug calorimeter from a gas detector system to one using scintillating tiles read out through wavelength shifting fibers. This upgrade is required to take advantage of the increase in luminosity which the Tevatron will provide in the future. The tile-fiber calorimeter; which is longitudinally segmented into electromagnetic and hadronic sections, will be read out through 1824 photomultiplier tubes. The performance requirements of the calorimeter demand that the PMTs have good response to light in the 500 nm region, provide adequate amplification for signals from minimum ionizing particles, provide linear response for peak anode currents up to 25 mA at a gain of 5 x 10(4), and fit into the restricted space at the rear of the plugs. For convenience, we also desire a single PMT and base combination be used for the electromagnetic and hadron calorimeters even though the required gains in these sections differ by a factor of 10. This paper describes the evaluation process used to determine the adequacy of the commercially available PMTs which appeared to meet our performance requirements. (C) 1998 Published by Elsevier Science B.V. All rights reserved. C1 Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Bologna, Dipartimento Fis, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Ist Nazl Fis Nucl, Padua, Italy. Univ Padua, Dipartimento Fis, Padua, Italy. Purdue Univ, Dept Phys, W Lafayette, IN 47904 USA. RP Gallinaro, M (reprint author), Univ Penn, Dept Phys, 209 S 33rd St, Philadelphia, PA 19104 USA. OI Gallinaro, Michele/0000-0003-1261-2277 NR 6 TC 1 Z9 1 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 21 PY 1998 VL 406 IS 1 BP 103 EP 116 DI 10.1016/S0168-9002(97)01193-5 PG 14 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZF078 UT WOS:000072860400010 ER PT J AU Ardelean, J Citterio, M Hrisoho, A Manfredi, PF Speziali, V Truong, K AF Ardelean, J Citterio, M Hrisoho, A Manfredi, PF Speziali, V Truong, K TI On the noise behaviour of DMILL charge and current-sensitive preamplifier architectures SO NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT LA English DT Article AB Novel configurations of current and voltage-sensitive preamplifiers in DMILL technology intended for calorimetry applications are discussed. A broad set of noise characterisation tests: including room temperature, cryogenic operation and radiation effects, is given. It is shown that in cryogenic conditions the noise behaviour is considerably less current dependent than at room temperature. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Pavia, Dipartimento Elettron, I-27100 Pavia, Italy. Lab Accelerateur Lineaire, F-91405 Orsay, France. Ist Nazl Fis Nucl, I-27100 Pavia, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Speziali, V (reprint author), Univ Pavia, Dipartimento Elettron, Via Ferrata 1, I-27100 Pavia, Italy. NR 3 TC 3 Z9 3 U1 1 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0168-9002 J9 NUCL INSTRUM METH A JI Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip. PD MAR 21 PY 1998 VL 406 IS 1 BP 127 EP 138 DI 10.1016/S0168-9002(97)01165-0 PG 12 WC Instruments & Instrumentation; Nuclear Science & Technology; Physics, Nuclear; Physics, Particles & Fields SC Instruments & Instrumentation; Nuclear Science & Technology; Physics GA ZF078 UT WOS:000072860400012 ER PT J AU Bershady, MA Trevese, D Kron, RG AF Bershady, MA Trevese, D Kron, RG TI Variable extended objects in Selected Area 57 SO ASTROPHYSICAL JOURNAL LA English DT Article DE galaxies, active; galaxies, photometry; galaxies, Seyfert; quasars, general; surveys ID ACTIVE GALACTIC NUCLEI; LUMINOSITY FUNCTION; COMPLETE SAMPLE; MULTICOLOR PHOTOMETRY; FAINT GALAXIES; QUASARS; VARIABILITY; CATALOG; FIELD; QSOS AB We have isolated a sample of 14 candidate variable objects with extended image structure to B-J = 22.5 in 0.284 deg(2) of Selected Area 57. The majority of candidates are blue (U-B < 0) and relatively compact. At fainter magnitudes, there is a steep rise in the number of variable objects. These objects are also compact and blue, and some of them are likely to be truly stellar. Twelve of the B-J less than or equal to 22.5 candidates have been observed spectroscopically over limited ranges of wavelength and a variety of resulting signal-to-noise ratios. Three of the four brightest have broad emission lines characteristic of Seyfert I galaxies. The fourth has a highly variable spectrum consistent with Seyfert-like activity. A fifth candidate has emission-line ratios nominally consistent with a Seyfert 2 galaxy. In most cases where we have not been able to confirm a Seyfert spectroscopic type, the spectra are of insufficient quality or coverage to rule out such a classification. Based on spectroscopic and photometric redshift information, the majority of candidates have luminosities less than 10% of the nominal demarcation between QSOs and active galactic nuclei (M-B = -23, H-o = 50 km s(-1) Mpc(-1), q(o) = 0.5). The surface density of confirmed M-B > -23 active galactic nuclei (AGNs) to B-J = 22, including stellar sources, is similar to 40 deg(-2), in good agreement with other surveys at this depth. The confirmed AGNs in extended sources make up 36% of this population. Thus, the application of a variability criterion to images with extended structure enhances the completeness of the census of active nuclei. If the majority of our candidates are bona fide AGNs, the surface density could be as high as 82 deg(-2) for M-B > -23 and 162 deg(-2) for all luminosities to B-J = 22, with extended sources contributing up to 33% of the total. C1 Penn State Univ, Dept Astron & Astrophys, University Pk, PA 16802 USA. Univ Wisconsin, Dept Astron, Madison, WI 53706 USA. Univ Rome La Sapienza, Ist Astron, I-00161 Rome, Italy. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. RP Bershady, MA (reprint author), Penn State Univ, Dept Astron & Astrophys, 525 Davey Lab, University Pk, PA 16802 USA. NR 26 TC 33 Z9 33 U1 0 U2 0 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 103 EP 116 DI 10.1086/305371 PN 1 PG 14 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900009 ER PT J AU Totani, T Sato, K Dalhed, HE Wilson, JR AF Totani, T Sato, K Dalhed, HE Wilson, JR TI Future detection of supernova neutrino burst and explosion mechanism SO ASTROPHYSICAL JOURNAL LA English DT Article DE elementary particles; galaxies, ISM; Magellanic Clouds; supernovae, general ID STELLAR-CORE COLLAPSE; II SUPERNOVAE; ELECTRON ANTINEUTRINO; SN1987A; MASS; ASTRONOMY; SIGNAL; STARS AB Future detection of a supernova neutrino burst by large underground detectors would give important information for the explosion mechanism of collapse-driven supernovae. We studied the statistical analysis for the future detection of a nearby supernova by using a numerical supernova model and realistic Monte Carlo simulations of detection by the Super-Kamiokande detector. Pile mainly discuss the detectability of the signatures of the delayed explosion mechanism in the time evolution of the (v) over bar(e) luminosity and spectrum. For a supernova at 10 kpc away from the Earth, we find not only that the signature is clearly discernible but also that the deviation of the energy spectrum from the Fermi-Dirac (FD) distribution can be observed. The deviation from the FD distribution would, if observed, provide a test for the standard picture of neutrino emission from collapse-driven supernovae. For the D = 50 kpc case, the signature of the delayed explosion is still observable, but statistical fluctuation is too large to detect the deviation from the FD distribution. We also propose a method for statistical reconstruction of the time evolution of v, luminosity and spectrum from data, by which we can get a smoother time evolution and smaller statistical errors than by a simple, time-binning analysis. This method is useful especially when the available number of events is relatively small, e.g., a supernova in the LMC or SMC. A neutronization burst of v(e)'s produces about five scattering events when D = 10 kpc, and this signal is difficult to distinguish from (v) over bar(e)p events. C1 Univ Tokyo, Dept Phys, Tokyo 113, Japan. Univ Tokyo, Res Ctr Early Universe, Tokyo 113, Japan. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. RP Univ Tokyo, Dept Phys, Tokyo 113, Japan. EM totani@utaphp2.phys.s.u-tokyo.ac.jp NR 38 TC 198 Z9 199 U1 0 U2 4 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 216 EP 225 DI 10.1086/305364 PN 1 PG 10 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900019 ER PT J AU Cox, AN AF Cox, AN TI Theoretical period changes in yellow giant pulsators SO ASTROPHYSICAL JOURNAL LA English DT Article DE Cepheids; globular clusters, individual (M15); stars, individual (alpha UMi); stars, interiors; stars, oscillations; stars, variables, RR Lyrae ID HORIZONTAL-BRANCH STARS; RR LYRAE STARS; GLOBULAR-CLUSTERS; VARIABLES; EVOLUTION; CEPHEIDS; M15 AB Period changes in RR Lyrae variables and Cepheids, known for more than 60 years, can possibly be explained by small changes in a helium composition gradient below the hydrogen and helium convection zones. The particular cases for the globular cluster M15 double-mode RR Lyrae variable V53 and the Cepheid Polaris are studied. For the last 80 years, the fundamental mode period of V53 has been decreasing while the overtone mode period in this same star has been increasing. The rather steady overtone mode period increase for Polaris stopped very recently, and the period now seems constant. Diffusive settling of helium in these kinds of stars has been known to be slight because of the two convection zones and the long diffusion timescale below them. But a small amount of helium settling, even before the star begins to pulsate, and then a dredge-up of just a little helium by an occasional overshooting can change surface layer structures and periods. This dredge-up can have a timescale as short as the convection turnover time, i.e., a few days. A slight helium dredge-up episode may now have temporarily stopped the decaying pulsations and period increase of Polaris. Such an episode cannot explain the double-mode V53 case, but possibly the helium composition gradient is deepened enough by matter accretion in only 80 years to explain its observed opposite period changes. Another mechanism that might be important for period changes is tidal mixing of the small composition gradients caused by occasional close encounters of stars in clusters. Significant stellar rotation would keep the surface layer composition homogeneous and not allow the anomalous period changes discussed here. C1 Los Alamos Natl Lab, Los Alamos, NM 87544 USA. RP Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87544 USA. NR 44 TC 14 Z9 14 U1 0 U2 0 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 246 EP 252 DI 10.1086/305376 PN 1 PG 7 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900022 ER PT J AU Bazan, G Arnett, D AF Bazan, G Arnett, D TI Two-dimensional hydrodynamics of pre-core collapse: Oxygen shell burning SO ASTROPHYSICAL JOURNAL LA English DT Article DE convection; hydrodynamics -; nuclear reactions, nucleosynthesis, abundances; stars, interiors; supernovae, general ID TURBULENT COMPRESSIBLE CONVECTION; PIECEWISE-PARABOLIC METHOD; DEEP ATMOSPHERE; POSTEXPLOSION HYDRODYNAMICS; STELLAR INTERIORS; SUPERNOVA EJECTA; II SUPERNOVAE; HELIUM FLASH; NEUTRON STAR; GAMMA-RAYS AB By direct hydrodynamic simulation, using the piecewise parabolic method code PROMETHEUS, we study the properties of a convective oxygen-burning shell in a SN 1987A progenitor star (20 M-.) prior to collapse. The convection is too heterogeneous and dynamic to be well approximated by one-dimensional diffusion-like algorithms that have previously been used for this epoch. Qualitatively new phenomena are seen. The simulations are two-dimensional, with good resolution in radius and angle, and used a large (90 degrees) slice centered at the equator. The microphysics and the initial model were carefully treated. Many of the qualitative features of previous multidimensional simulations of convection are seen, including large kinetic and acoustic energy fluxes, which are not accounted for by mixing length theory. Small but significant amounts of C-12 are mixed nonuniformly into the oxygen-burning convection zone, resulting in hot spots of nuclear energy production that are more than an order of magnitude more energetic than the oxygen flame itself, Density perturbations (up to 8%) occur at the "edges" of the convective zone and are the result of gravity waves generated by interaction of penetrating flows into the stable region. Perturbations of temperature and Y-e(or neutron excess eta) at the base of the convective zone are of sufficient magnitude to create angular inhomogeneities in explosive nucleosynthesis products and need to be included in quantitative estimates of yields. Combined with the plumelike velocity structure arising from convection, the perturbations will contribute to the mixing of Ni-56 throughout supernovae envelopes. Runs of different resolution and angular extent were performed to test the robustness of these simulations. C1 Univ Arizona, Steward Observ, Tucson, AZ 85721 USA. RP Bazan, G (reprint author), Univ Calif Lawrence Livermore Natl Lab, POB 808,L-170, Livermore, CA 94550 USA. NR 79 TC 98 Z9 98 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 316 EP 332 DI 10.1086/305346 PN 1 PG 17 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900029 ER PT J AU Sion, EM Cheng, FH Szkody, P Sparks, W Gansicke, B Huang, M Mattei, J AF Sion, EM Cheng, FH Szkody, P Sparks, W Gansicke, B Huang, M Mattei, J TI Anomalous cooling of the massive white dwarf in U Geminorum following a narrow dwarf nova outburst SO ASTROPHYSICAL JOURNAL LA English DT Article DE novae, cataclysmic variables; stars, abundances; stars, individual (U Geminorum); ultraviolet, stars; white dwarfs ID CATACLYSMIC VARIABLES AB We obtained Hubble Space Telescope Goddard High-Resolution Spectrograph medium-resolution (G160M grating), phase-resolved spectroscopic observations of the prototype dwarf nova U Geminorum during dwarf nova quiescence, 13 days and 61 days following the end of a narrow outburst. The spectral wavelength ranges were centered on three different line regions: N v (1238 Angstrom 1242 Angstrom), Si III (1300 Angstrom), and He II (1640 Angstrom). All of the quiescent spectra at both epochs are dominated by absorption lines and show no emission features. The Si III and He II absorption-line velocities versus orbital phase trace the orbital motion of the white dwarf, but the N v absorption velocities appear to deviate from the white dwarf motion. We confirm our previously reported low white dwarf rotational velocity, V sin i = 100 km s(-1). We obtain a white dwarf orbital velocity semiamplitude K-1 = 107 km s(-1). Using the gamma-velocity of Wade, we obtain an Einstein redshift of 80.4 km s(-1) and hence a carbon core white dwarf mass of similar to 1.1 M-.. We report the first subsolar chemical abundances of C and Si for U Gem with C/H = 0.05 times solar, almost certainly a result of C depletion due to thermonuclear processing. This C depletion is discussed within the framework of a weak thermonuclear runaway, contamination of the secondary during the common envelope phase, and mixing of C-depleted white dwarf gas with C-depleted matter deposited during a dwarf nova event. Remarkably, the T-eff of the white dwarf 13 days after outburst is only 32,000 K, anomalously cooler than previous early postoutburst measurements. Extensive cooling during an extraordinarily long (210 days) quiescence followed by accretion onto an out-of-equilibrium cooled degenerate could explain the lower T-eff. C1 Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. Univ Sci & Technol China, Ctr Astrophys, Hefei 230026, Anhui, Peoples R China. Univ Washington, Dept Astron, Seattle, WA 98195 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM USA. Univ Sternwarte Gottingen, D-37083 Gottingen, Germany. Arthur Andersen Inc, New York, NY 10103 USA. Amer Assoc Variable Star Observers, Cambridge, MA USA. RP Sion, EM (reprint author), Villanova Univ, Dept Astron & Astrophys, Villanova, PA 19085 USA. EM emsion@ucis.vill.edu; fhcheng@ucis.vill.edu; szkody@astro.washington.edu; wsparks@lanl.gov; boris@uni-ew.gwdg.de; min.a.huang@arthurandersen.com; aavso@aavso.org RI Gaensicke, Boris/A-9421-2012 OI Gaensicke, Boris/0000-0002-2761-3005 NR 20 TC 47 Z9 47 U1 0 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 449 EP 453 DI 10.1086/305378 PN 1 PG 5 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900038 ER PT J AU Blinnikov, SI Eastman, R Bartunov, OS Popolitov, VA Woosley, SE AF Blinnikov, SI Eastman, R Bartunov, OS Popolitov, VA Woosley, SE TI A comparative modeling of supernova 1993J SO ASTROPHYSICAL JOURNAL LA English DT Article DE hydrodynamics; methods, numerical; radiative transfer; stars, individual (SN 1993J); supernovae ID THEORETICAL LIGHT CURVES; RADIATIVE-TRANSFER; II SUPERNOVAE; THERMODYNAMIC-EQUILIBRIUM; SPECTRAL-LINES; OPACITY; ATMOSPHERES; STARS; EXCITATION; SN-1993J AB The light curve of supernova (SN) 1993J is calculated using two approaches to radiation transport as exemplified by the two computer codes, STELLA and EDDINGTON. Particular attention is paid to shock breakout and the photometry in the U, B, and V bands during the first 120 days. The hydrodynamical model, the explosion of a 13 M-. star that has lost most of its hydrogenic envelope to a companion, is the same in each calculation. The comparison elucidates differences between the approaches and also serves to validate the results of both. STELLA includes implicit hydrodynamics and is able to model supernova evolution at early times, before the expansion is homologous. STELLA also employs multigroup photonics and is able to follow the radiation as it decouples from the matter. EDDINGTON uses a different algorithm for integrating the transport equation, assumes homologous expansion, and uses a finer frequency resolution. Good agreement is achieved between the two codes only when compatible physical assumptions are made about the opacity. In particular, the line opacity near the principal (second) peak of the light curve must be treated primarily as absorptive, even though the electron density is too small for collisional deexcitation to be a dominant photon destruction mechanism. Justification is given for this assumption and involves the degradation of photon energy by "line splitting," i.e., fluorescence. The fact that absorption versus scattering matters to the light curve is indicative of the fact that departures from equilibrium radiative diffusion are important. A new result for SN 1993J is a prediction of the continuum spectrum near the shock breakout (calculated by STELLA), which is superior to the results of other standard single energy group hydrocodes such as VISPHOT or TITAN. Based on the results of our independent codes, we discuss the uncertainties involved in the current time-dependent models of supernova light curves. C1 Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. Inst Theoret & Expt Phys, Moscow 117259, Russia. Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Moscow MV Lomonosov State Univ, Sternberg Astron Inst, Moscow 119899, Russia. RP Univ Calif Santa Cruz, Univ Calif Observ, Lick Observ, Santa Cruz, CA 95064 USA. EM blinn@sai.msu.su; eastman@tapestry.llnl.gov; oleg@sai.msu.su; vlad@sai.msu.su; woosley@ucolick.org NR 66 TC 104 Z9 106 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X EI 1538-4357 J9 ASTROPHYS J JI Astrophys. J. PD MAR 20 PY 1998 VL 496 IS 1 BP 454 EP 472 DI 10.1086/305375 PN 1 PG 19 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZE341 UT WOS:000072782900039 ER PT J AU Thompson, DN Hames, BR Reddy, CA Grethlein, HE AF Thompson, DN Hames, BR Reddy, CA Grethlein, HE TI In vitro degradation of natural insoluble lignin in aqueous media by the extracellular peroxidases of Phanerochaete chrysosporium SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE lignin peroxidase; manganese peroxidase; LIP; MNP; Phanerochaete chrysosporium ID TRANSFORM INFRARED SPECTROMETRY; ORGANIC-ACID CHELATORS; MANGANESE PEROXIDASE; OXIDATIVE CLEAVAGE; MODEL DIMER; MECHANISM; PRETREATMENT AB The lignin peroxidases (LIP) and manganese peroxidases (MNP) of Phanerochaete chrysosporium catalyze a wide range of lignin depolymerization reactions with lignin models and synthetic lignins in solution. However, their ability to degrade insoluble natural lignin in aqueous media has not been demonstrated. Insoluble isolated poplar lignin similar to natural lignin was treated in vitro in aqueous media for 12 h with LIP, MNP, and both. Treatment with MNP alone slightly increased the solid mass and produced measurable amounts of lignin-derived 2,6-dimethoxyhydroquinone and 2-methoxyhydroquinone but did not appreciably decrease the total lignin content. Treatment with LIP alone did not decrease the mass but produced measurable amounts of lignin-derived p-hydroxybenzoic acid and slightly decreased the lignin content. Finally, treatment with LIP and MNP together decreased the solid mass by 11%, decreased the lignin content by 5%, and released low-concentration compounds with mass spectra containing the typical lignin-derived electron-impact fragments of mass 107, 137, 151, 167, and 181. These results suggest that MNP increases the effectiveness of LIP-mediated lignin degradation. (C) 1998 John Wiley & Sons, Inc. C1 Michigan State Univ, Dept Chem Engn, E Lansing, MI 48824 USA. Michigan State Univ, NSF, Ctr Microbial Ecol, E Lansing, MI 48824 USA. Natl Renewable Energy Lab, Biomass Anal Grp, Golden, CO 80401 USA. Michigan State Univ, Dept Microbiol, E Lansing, MI 48824 USA. Michigan Biotechnol Inst, Lansing, MI 48909 USA. RP Idaho Natl Lab, Dept Biotechnol, POB 1625, Idaho Falls, ID 83415 USA. NR 39 TC 19 Z9 19 U1 0 U2 9 PU WILEY-BLACKWELL PI HOBOKEN PA 111 RIVER ST, HOBOKEN 07030-5774, NJ USA SN 0006-3592 EI 1097-0290 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD MAR 20 PY 1998 VL 57 IS 6 BP 704 EP 717 DI 10.1002/(SICI)1097-0290(19980320)57:6<704::AID-BIT8>3.0.CO;2-P PG 14 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA YU871 UT WOS:000071764400008 PM 10099250 ER PT J AU Weaver, VM Wang, F Bissell, MJ AF Weaver, VM Wang, F Bissell, MJ TI Alterations in tissue structure and loss of coordinated growth and adhesion in breast cancer SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Life Sci, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 20 PY 1998 VL 12 IS 5 SU S MA 3660 BP A630 EP A630 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HD UT WOS:000076006500044 ER PT J AU Yasumura, S Ma, R Talluri, A AF Yasumura, S Ma, R Talluri, A TI Correlation between appendicular muscle volumes as determined by bioelectrical impedance analysis (BIA) and total body potassium (TBK) in healthy adults. SO FASEB JOURNAL LA English DT Meeting Abstract C1 Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. Akern, I-50127 Florence, Italy. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 20 PY 1998 VL 12 IS 5 SU S MA 3784 BP A651 EP A651 PN 2 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HD UT WOS:000076006500167 ER PT J AU Marshall, SL AF Marshall, SL TI Convergence acceleration of Fourier series by analytical and numerical application of Poisson's formula SO JOURNAL OF PHYSICS A-MATHEMATICAL AND GENERAL LA English DT Article ID MOLECULAR-POLARIZATION; ADSORBED MONOLAYERS; ELECTRODES; COEFFICIENTS; DIPOLES; IONS AB A form of the Poisson summation formula appropriate for the transformation of infinite Fourier series is derived and shown to be applicable to slowly converging series arising in the solution of Laplace's equation in a rectangular electrochemical cell. The result is a rapidly convergent Fourier series which is particularly useful in giving the potential close to the electrode surface. Results obtained from the analytical expression are found to be in close agreement with those resulting from numerical evaluation of the Fourier integrals (using Simpson's rule and the Euler transformation) and direct summation by using Goertzel's (1958) algorithm. C1 Univ Natal, Dept Chem, ZA-3209 Pietermartizburg, South Africa. RP Marshall, SL (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Marshall, Simon/E-9518-2010 NR 44 TC 5 Z9 5 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0305-4470 J9 J PHYS A-MATH GEN JI J. Phys. A-Math. Gen. PD MAR 20 PY 1998 VL 31 IS 11 BP 2691 EP 2704 DI 10.1088/0305-4470/31/11/016 PG 14 WC Physics, Multidisciplinary; Physics, Mathematical SC Physics GA ZE519 UT WOS:000072801000016 ER PT J AU Prouteau, C Duscher, G Browning, ND Pennycook, SJ AF Prouteau, C Duscher, G Browning, ND Pennycook, SJ TI Investigation of the local superconducting properties in Ag-sheathed BSCCO tapes by STEM SO PHYSICA C LA English DT Article DE tapes; grain boundaries; hole concentration; Z-contrast; EELS ID ELECTRON-ENERGY-LOSS; YBA2CU3O7-DELTA GRAIN-BOUNDARIES; HIGH-TC SUPERCONDUCTORS; OXYGEN-K-EDGE; LOSS SPECTROSCOPY; CRITICAL CURRENTS; MODEL; TRANSPORT; SYMMETRY; DENSITY AB Grain boundaries in Ag-sheathed (Bi/Pb)(2)Sr2Ca2Cu3O10 tapes are investigated on the atomic scale, using a combination of Z-contrast imaging and electron energy loss spectroscopy in the scanning transmission electron microscope. The oxygen K and the copper L-2,L-3 ionization edges are studied to determine the copper valence at grain boundaries in two tapes exhibiting different critical current densities (J(c)). The lower J(c) tape contains precipitates at high angle grain boundaries which appear to cause the formation of an extended non-stoichiometric zone, depleted in oxygen, and where the copper valence is less than or equal +1. In the higher J(c) tape, no reduction in copper valence is found at the high angle grain boundaries, indicating no depletion zone and suggesting improved transport properties. Thus, a correlation is found between the quality of the grain boundaries, the presence of other phases, and the overall J(c) of the tapes. (C) 1998 Elsevier Science B.V. C1 Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37381 USA. RP Prouteau, C (reprint author), Univ Illinois, Dept Phys, Chicago, IL 60607 USA. RI Duscher, Gerd/G-1730-2014; OI Duscher, Gerd/0000-0002-2039-548X; Browning, Nigel/0000-0003-0491-251X NR 39 TC 5 Z9 5 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAR 20 PY 1998 VL 298 IS 1-2 BP 1 EP 9 DI 10.1016/S0921-4534(98)00012-4 PG 9 WC Physics, Applied SC Physics GA ZM021 UT WOS:000073496800001 ER PT J AU Zhu, YT Baldonado, PS Peterson, EJ Park, YS Manthiram, A Butt, DP Peterson, DE Mueller, FM AF Zhu, YT Baldonado, PS Peterson, EJ Park, YS Manthiram, A Butt, DP Peterson, DE Mueller, FM TI Variation of oxygen content and crystal chemistry of YBa4Cu3O8.5+delta SO PHYSICA C LA English DT Article DE crystal chemistry; oxygen content; thermogravimetric analysis (TGA) ID COPPER-OXIDE SUPERCONDUCTORS; PHASE COMPATIBILITIES; SYSTEM Y2O3-BAO-CUO; 950-DEGREES-C AB All phases discovered so far in the Y-Ba-Cu-O system have layered (2-dimensional) structures with the exception of YBa4Cu3O8.5+delta (Y143), which has a cubic (3-dimensional) structure, In an attempt to understand the crystal chemistry of the Y143 phase and to make it superconductive, the Y143 compound has been treated at 450 degrees C in oxygen and subsequently annealed at several different temperatures in a nitrogen atmosphere. The samples have been characterized by X-ray diffraction, thermogravimetric analysis (TGA), iodometric titration, and SQUID magnetometer measurements. The Y143 phase was found to be nonsuperconductive for all annealing conditions, The oxygen content was found to decrease with increasing annealing temperature in two steps, corresponding to the loss of oxygen from two different lattice sites. The lattice parameter decreased during the first step and increased during the second step with increasing annealing temperature or with decreasing oxygen content. Rietveld refinement of X-ray powder diffraction data showed that the O3 and O4 sites, which are geometrically identical within the crystal lattice, have an equal occupancy of 51.5% in samples not annealed in N-2. However, when samples were annealed in N-2, an oxygen redistribution from the O4 site to the O3 site occurred during the low temperature (< 500 degrees C) oxygen loss step. The variation in oxygen content and crystal chemistry has been explained on the basis of the unique crystal structure of Y143 and the internal stresses on the metal-oxygen bonds. (C) 1998 Elsevier Science B.V. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. Univ Texas, Ctr Mat Sci & Engn, Austin, TX 78712 USA. RP Zhu, YT (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, MS G755, Los Alamos, NM 87545 USA. RI Zhu, Yuntian/B-3021-2008; Butt, Darryl/B-7480-2008 OI Zhu, Yuntian/0000-0002-5961-7422; Butt, Darryl/0000-0003-4501-8864 NR 17 TC 5 Z9 6 U1 2 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAR 20 PY 1998 VL 298 IS 1-2 BP 29 EP 36 DI 10.1016/S0921-4534(98)00013-6 PG 8 WC Physics, Applied SC Physics GA ZM021 UT WOS:000073496800004 ER PT J AU Polyak, VJ McIntosh, WC Guven, N Provencio, P AF Polyak, VJ McIntosh, WC Guven, N Provencio, P TI Age and origin of Carlsbad cavern and related caves from Ar-40/Ar-39 of alunite SO SCIENCE LA English DT Article ID POTASSIUM-ARGON; NORTH-AMERICA; KENYA RIFT; NEVADA; GEOCHRONOLOGY AB Ar-40/Ar-39 dating of fine-grained alunite that formed during cave genesis provides ages of formation for the Big Room level of Carlsbad Cavern [4.0 to 3.9 million years ago (Ma)], the upper level of Lechuguilla Cave (6.0 to 5.7 Ma), and three other hypogene caves (11.3 to 6.0 Ma) in the Guadalupe Mountains of New Mexico. Alunite ages increase and are strongly correlative with cave elevations, which indicates an 1100-meter decline in the water table, apparently related to tectonic uplift and tilting, from 11.3 Ma to the present. Ar-40/Ar-39 dating studies of the hypogene caves have the potential to help resolve late Cenozoic climatic, speleologic, and tectonic questions. C1 Texas Tech Univ, Dept Geosci, Lubbock, TX 79409 USA. New Mexico Inst Min & Technol, New Mexico Geochronol Res Lab, Socorro, NM 87801 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Polyak, VJ (reprint author), Texas Tech Univ, Dept Geosci, Lubbock, TX 79409 USA. NR 43 TC 62 Z9 63 U1 1 U2 10 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 20 PY 1998 VL 279 IS 5358 BP 1919 EP 1922 DI 10.1126/science.279.5358.1919 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZC748 UT WOS:000072613300042 ER PT J AU Romesberg, FE Spiller, B Schultz, PG Stevens, RC AF Romesberg, FE Spiller, B Schultz, PG Stevens, RC TI Immunological origins of binding and catalysis in a Diels-Alderase antibody SO SCIENCE LA English DT Article ID TOXIN PEPTIDE COMPLEX; CHORISMATE MUTASE; CRYSTAL-STRUCTURE; MOLECULAR REPLACEMENT; ACTIVE-SITE; RESOLUTION; DIVERSITY; PROTEINS; FAMILY; GENES AB The three-dimensional structure of an antibody (39-A11) that catalyzes a Diels-Alder reaction has been determined, The structure suggests that the antibody catalyzes this pericyclic reaction through a combination of packing and hydrogen-bonding interactions that control the relative geometries of the bound substrates and electronic distribution in the dienophile. A single somatic mutation, serine-91 of the light chain to valine, is largely responsible for the increase in affinity and catalytic activity of the affinity-matured antibody. Structural and functional studies of the germ-line precursor suggest that 39-A11 and related antibodies derive from a family of germ-line genes that have been selected throughout evolution for the ability of the encoded proteins to form a polyspecific combining site. Germ line-encoded antibodies of this type, which can rapidly evolve into high-affinity receptors for a broad range of structures, may help to expand the binding potential associated with the structural diversity of the primary antibody repertoire. C1 Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. RP Schultz, PG (reprint author), Univ Calif Berkeley, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RI Stevens, Raymond/K-7272-2015 OI Stevens, Raymond/0000-0002-4522-8725 NR 41 TC 127 Z9 127 U1 0 U2 15 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 20 PY 1998 VL 279 IS 5358 BP 1929 EP 1933 DI 10.1126/science.279.5358.1929 PG 5 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZC748 UT WOS:000072613300045 PM 9506942 ER PT J AU Brodsky, SJ Schmidt, I AF Brodsky, SJ Schmidt, I TI Polarization asymmetry zero in heavy quark photoproduction and leptoproduction SO PHYSICS LETTERS B LA English DT Article ID DEPENDENT PARTON DISTRIBUTIONS; GLUONIC CONTRIBUTION; NONPERTURBATIVE QCD; INTRINSIC CHARM; PROTON SPIN; SCATTERING; MODEL AB We demonstrate two novel features of the sea-quark contributions to the polarized structure functions and photoproduction cross sections, a zero sum rule and a zero crossing point of the polarization asymmetry, which can be traced directly to the dynamics of the perturbative tree-graph gluon-splitting contributions. In particular, we show that the Born contribution of massive quarks arising from photon-gluon fusion gives zero contribution to the logarithmic integral over the polarization asymmetry fdv/v Delta sigma(v,Q(2)) for any photon virtuality, The vanishing of this integral in the Bjorken scaling limit then implies a zero gluon-splitting Born contribution to the Gourdin-Ellis-Jaffe sum rule for polarized structure functions from massive sea quarks. The vanishing of the polarization asymmetry at or near the canonical position predicted by perturbative QCD provides an important tool for verifying the dominance of the photon-gluon fusion contribution to charm photoproduction and for validating the effectiveness of this process as a measure of the gluon polarization Delta G(x,Q(2)) in the nucleon. The displacement of the asymmetry zero from its canonical position is sensitive to the virtuality of the gluon in the photon-gluon fusion subprocess, and it can provide a measure of intrinsic and higher-order sea quark contributions. (C) 1998 Published by Elsevier Science B.V. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. Univ Tecn Federico Santa Maria, Dept Fis, Valparaiso, Chile. RP Brodsky, SJ (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RI Schmidt, Ivan/J-5920-2012 NR 39 TC 3 Z9 3 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 19 PY 1998 VL 423 IS 1-2 BP 145 EP 150 DI 10.1016/S0370-2693(98)00099-9 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK630 UT WOS:000073344600023 ER PT J AU Abele, A Adomeit, J Amsler, C Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Beuchert, K Bischoff, S Blum, P Braune, K Bugg, DV Case, T Cramer, O Crede, V Crowe, KM Degener, T Djaoshvili, N von Dombrowski, S Doser, M Dunnweber, W Ehmanns, A Engelhardt, D Faessler, MA Giarritta, P Haddock, RP Heinsius, FH Heinzelmann, M Herbstrith, A Herz, M Hessey, NP Hidas, P Hodd, C Holtzhaussen, C Huttmann, K Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kolo, C Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H McCrady, R Meier, J Meyer, CA Montanet, L Ouared, R Ould-Saada, F Peters, K Pick, B Pietra, C Pinder, CN Ratajczak, M Regenfus, C Resag, S Roethel, W Schmidt, P Scott, I Seibert, R Spanier, S Stock, H Strassburger, C Strohbusch, U Suffert, M Thoma, U Tischhauser, M Volcker, C Wallis, S Walther, D Wiedner, U Wittmack, K Zou, BS Zupancic, C AF Abele, A Adomeit, J Amsler, C Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Beuchert, K Bischoff, S Blum, P Braune, K Bugg, DV Case, T Cramer, O Crede, V Crowe, KM Degener, T Djaoshvili, N von Dombrowski, S Doser, M Dunnweber, W Ehmanns, A Engelhardt, D Faessler, MA Giarritta, P Haddock, RP Heinsius, FH Heinzelmann, M Herbstrith, A Herz, M Hessey, NP Hidas, P Hodd, C Holtzhaussen, C Huttmann, K Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kolo, C Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H McCrady, R Meier, J Meyer, CA Montanet, L Ouared, R Ould-Saada, F Peters, K Pick, B Pietra, C Pinder, CN Ratajczak, M Regenfus, C Resag, S Roethel, W Schmidt, P Scott, I Seibert, R Spanier, S Stock, H Strassburger, C Strohbusch, U Suffert, M Thoma, U Tischhauser, M Volcker, C Wallis, S Walther, D Wiedner, U Wittmack, K Zou, BS Zupancic, C CA Crystal Barrel Collaboration TI Exotic eta pi state in (p)over-bar-d annihilation at rest into pi(-)pi(0)eta p(spectator) SO PHYSICS LETTERS B LA English DT Article ID RESONANCE; GEV/C; WAVE AB With antiprotons slopped in liquid deuterium, the <(p)over bar n> annihilation channel pi(-)pi(0) eta was studied using a final sample of 52 576 events obtained for a spectator proton momentum < 100 MeV/c. In the intensity distribution the eta pi P-wave is clearly apparent by its interferences with the dominant rho(-)(770) rind a(2)(1310) two-meson resonances. A partial wave analysis of the data yields evidence for resonant behaviour of the eta pi P-wave, which has the non- quantum numbers I-G = 1(-), J(PC) = 1(-+). The extracted Breit-Wigner resonance parameters are m = (1400 +/- 20 +/- 20) MeV/c(2) and Gamma = (310 +/- 50(-30)(+50)) MeV/c(2). (C) 1998 Published by Elsevier Science B.V. C1 Univ Karlsruhe, D-76021 Karlsruhe, Germany. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Univ Bonn, D-53115 Bonn, Germany. Hungarian Acad Sci, H-1525 Budapest, Hungary. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CERN, CH-1211 Geneva 4, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Univ London Queen Mary & Westfield Coll, London E1 4NS, England. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Munchen, D-80333 Munchen, Germany. Univ Paris 06, LPNHE, F-75252 Paris, France. Univ Paris 07, LPNHE, F-75252 Paris, France. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ctr Rech Nucl, F-67037 Strasbourg, France. Univ Zurich, CH-8057 Zurich, Switzerland. RP Abele, A (reprint author), Univ Karlsruhe, D-76021 Karlsruhe, Germany. NR 34 TC 197 Z9 199 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 19 PY 1998 VL 423 IS 1-2 BP 175 EP 184 DI 10.1016/S0370-2693(98)00123-3 PG 10 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK630 UT WOS:000073344600028 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NK Cremaldi, LM Darling, C Denisenko, K Fernandez, A Fox, GF Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yi, D Yoshida, S Zaliznyak, R Zhang, C CA Fermilab E791 Collaboration TI Study of the decay D-0 -> K-K+pi(-)pi(-) SO PHYSICS LETTERS B LA English DT Article ID D-MESONS; SYSTEM AB Using data from Fermilab fixed-target experiment E791, we measure the branching ratio for D-0 --> K-K+ pi(-)pi(+) and its resonant components. We find Gamma(D-0 --> K-K+ pi(-)pi(+))/Gamma(D-0 --> K- pi(+)pi(-)pi(+))=(3.13 +/- 0.37 +/- 0.36)%. A coherent amplitude analysis is used to estimate the resonant components. We measure the ratios Gamma(D-0 --> f)/Gamma(D-0 --> K- pi(+)pi(-)pi(+)) to be (2.0 +/- 0.9 +/- 0.8)% for f = phi rho(0), (0.9 +/- 0.4 +/- 0.5)% for f = phi pi(+)pi(-), < 2.0% at the 90% CL for f = K-*0(892)(K) over bar(*0)(892), and < 1.0% at the 90% CL for f = <(K)over bar(*0)>(892)K(+)pi(-) or K-*0(892)K(-)pi(+). (C) 1998 Published by Elsevier Science B.V. C1 Univ Mississippi, University, MS 38677 USA. Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. CINVESTAV, Mexico City 14000, DF, Mexico. Fermilab Astrophys Ctr, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Massachusetts, Amherst, MA 01003 USA. Ohio State Univ, Columbus, OH 43210 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Mexico City, DF, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Univ Mississippi, University, MS 38677 USA. RI Anjos, Joao/C-8335-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016; de Mello Neto, Joao/C-5822-2013 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; de Mello Neto, Joao/0000-0002-3234-6634 NR 23 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 19 PY 1998 VL 423 IS 1-2 BP 185 EP 193 DI 10.1016/S0370-2693(98)00066-5 PG 9 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK630 UT WOS:000073344600029 ER PT J AU Bocher, M Kusubov, N Nordahl, TE AF Bocher, M Kusubov, N Nordahl, TE TI Seasonal variations of cerebral hemispheric asymmetry SO JOURNAL OF COGNITIVE NEUROSCIENCE LA English DT Meeting Abstract C1 Univ Calif Davis, Dept Psychiat, Davis, CA USA. LBNL, Ctr Funct Imaging, Berkeley, CA USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU MIT PRESS PI CAMBRIDGE PA 55 HAYWARD STREET, CAMBRIDGE, MA 02142 USA SN 0898-929X J9 J COGNITIVE NEUROSCI JI J. Cogn. Neurosci. PD MAR 18 PY 1998 VL 10 SU S BP 104 EP 104 PG 1 WC Neurosciences; Psychology, Experimental SC Neurosciences & Neurology; Psychology GA ZJ263 UT WOS:000073196500302 ER PT J AU Dimri, GP Campisi, J AF Dimri, GP Campisi, J TI Extension of replicative life span and induction of crisis in E6 expressing fibroblasts by overexpression of E2F1 SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Berkeley, Dept Canc Biol, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. NR 0 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 1846 BP A317 EP A317 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006401842 ER PT J AU Dueker, SR Clifford, AJ Lame, MW Segall, HJ Buchholz, BA Vogel, JS AF Dueker, SR Clifford, AJ Lame, MW Segall, HJ Buchholz, BA Vogel, JS TI Production of carbon-14 labeled phytonutrients in spinach for human nutrition studies employing accelerator mass spectrometry detection SO FASEB JOURNAL LA English DT Meeting Abstract C1 Univ Calif Davis, Dept Nutr & Mol Biosci, Davis, CA USA. Univ Calif Lawrence Livermore Natl Lab, CAMS, Livermore, CA 94551 USA. RI Buchholz, Bruce/G-1356-2011 NR 0 TC 5 Z9 5 U1 0 U2 1 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 1227 BP A210 EP A210 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006401222 ER PT J AU Onaivi, ES Stubbs, L Chakrabarti, A Chittenden, L Hurst, DP Akinshola, BE Shire, D Reggio, PH AF Onaivi, ES Stubbs, L Chakrabarti, A Chittenden, L Hurst, DP Akinshola, BE Shire, D Reggio, PH TI Murine cannabinoid receptor genetics SO FASEB JOURNAL LA English DT Meeting Abstract C1 Vanderbilt Univ, Sch Med, Nashville, TN 37232 USA. NRI, Nashville, TN 37232 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Kennesaw State Coll, Marietta, GA 30144 USA. Howard Univ, Coll Med, Washington, DC 20059 USA. Sanofi Rech, Labege, France. NR 0 TC 2 Z9 2 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 1129 BP A194 EP A194 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006401128 ER PT J AU Vieira, NE Goans, RE Weiss, GH Marini, JC Hopkins, E Yergey, AL AF Vieira, NE Goans, RE Weiss, GH Marini, JC Hopkins, E Yergey, AL TI Calcium kinetics in children with Osteogenesis imperfecta type III and IV: Pre- and post-growth hormone therapy SO FASEB JOURNAL LA English DT Meeting Abstract C1 NICHD, NIH, Bethesda, MD 20892 USA. NIH, DCRT, Bethesda, MD 20892 USA. Oak Ridge Associated Univ, REACTS, Oak Ridge, TN 37716 USA. NR 1 TC 0 Z9 0 U1 0 U2 0 PU FEDERATION AMER SOC EXP BIOL PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814-3998 USA SN 0892-6638 J9 FASEB J JI Faseb J. PD MAR 17 PY 1998 VL 12 IS 4 SU S MA 3174 BP A547 EP A547 PN 1 PG 1 WC Biochemistry & Molecular Biology; Biology; Cell Biology SC Biochemistry & Molecular Biology; Life Sciences & Biomedicine - Other Topics; Cell Biology GA 121HC UT WOS:000076006403171 ER PT J AU Zaera, F Salmeron, M AF Zaera, F Salmeron, M TI Coadsorption of sulfur and carbon monoxide on platinum single-crystal surfaces studied by scanning tunneling microscopy SO LANGMUIR LA English DT Article; Proceedings Paper CT Symposium in Honor of Brian Bent at the 213rd American-Chemical-Society National Meeting CY APR, 1997 CL SAN FRANCISCO, CALIFORNIA ID PT(111) SURFACE; CATALYTIC-OXIDATION; INDUCED RECONSTRUCTION; CO ADSORPTION; VELOCITY DISTRIBUTIONS; THERMAL-DESORPTION; MOLECULAR-BEAM; OXYGEN; ENERGY; SYSTEM AB The spatial distribution of sulfur and carbon monoxide coadsorbed on stepped Pt(lll) surfaces was characterized by low-energy electron diffraction and scanning tunneling microscopy. The formation of a p(2 x 2) sulfur overlayer on the platinum substrate leads to the slow doubling of the original monatomic steps, but subsequent room temperature exposure of that surface to CO removes the reconstruction and induces the formation of approximately 50 Angstrom wide intermediate steps covered with carbon monoxide exclusively. Additional CO dosing causes the development of more complex structures at the edge of the steps, where the excess sulfur is pushed to the bottom of the step while the rest of the terrace becomes covered with CO + S intermixed layers. The implications of these results for catalysis are briefly discussed. C1 Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Zaera, F (reprint author), Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA. RI Zaera, Francisco/J-8720-2013 NR 36 TC 12 Z9 13 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 17 PY 1998 VL 14 IS 6 BP 1312 EP 1319 DI 10.1021/la970739v PG 8 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZD421 UT WOS:000072683500005 ER PT J AU Jenks, CJ Thiel, PA AF Jenks, CJ Thiel, PA TI Quasicrystals: A short review from a surface science perspective SO LANGMUIR LA English DT Article; Proceedings Paper CT Symposium in Honor of Brian Bent at the 213rd American-Chemical-Society National Meeting CY APR, 1997 CL SAN FRANCISCO, CALIFORNIA ID QUASI-CRYSTALLINE COATINGS; SINGLE-GRAIN; AL68PD23MN9; ALLOYS; SIZE; APPROXIMANTS; OXIDATION; STRENGTH; ALUMINA; FILMS AB Quasicrystals are materials of both intellectual and practical importance. Although some level of understanding can now be applied to their bulk electronic and atomic structure, the same cannot be said of their surface properties. In this article, we point out some of the key issues in the surface science of quasicrystals at present. C1 Iowa State Univ, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Jenks, CJ (reprint author), Iowa State Univ, Dept Chem, Ames, IA 50011 USA. NR 65 TC 28 Z9 28 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 17 PY 1998 VL 14 IS 6 BP 1392 EP 1397 DI 10.1021/la970727+ PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZD421 UT WOS:000072683500018 ER PT J AU Yang, MX Gracias, DH Jacobs, PW Somorjai, GA AF Yang, MX Gracias, DH Jacobs, PW Somorjai, GA TI Lithographic fabrication of model systems in heterogeneous catalysis and surface science studies SO LANGMUIR LA English DT Article; Proceedings Paper CT Symposium in Honor of Brian Bent at the 213rd American-Chemical-Society National Meeting CY APR, 1997 CL SAN FRANCISCO, CALIFORNIA ID MICROSCOPE AB Lithographic technologies are applied to fabricate model systems for surface science and heterogeneous catalysis studies. An ordered metal nanocluster array fabricated on oxide substrates is also an ideal model system of supported industrial catalysts. Taking advantage of an ordered nanocluster array fabricated by electron beam lithography, the thermal and chemical stability of supported silver catalysts are examined in both oxidizing and reducing conditions. In reducing conditions, the supported silver nanoparticles are stable up to similar to 700 degrees C. In oxidizing conditions, however, the silver nanoparticles are oxidized below 200 degrees C, and conglomerate to micrometer-size amorphous clusters similar to 400 degrees C. The supported nanocluster sample can also be adapted to study reactivity of supported metal catalysts, as confirmed by measurement of ethylene hydrogenation turnover rates on platinum nanoparticle samples. Lithographic technologies can also fabricate model systems for other surface science research. A nanometer scale pattern is created on a poly(methyl methacrylate) (PMMA) surface by electron beam lithography. The sample is adapted to test a recent development in nanotribology, in which sm face elastic modulus (hardness) is determined by a modified atomic force microscope. In addition, lithographically fabricated supported nanostructures are used to image the AFM tip (thereby determining the radius of curvature of the tip), which is a critical parameter for the quantification of surface mechanical properties such as elastic modulus. Finally, taking advantage of the uniform height profile of lithographically fabricated nanostructures, ion sputtering yield can be determined by the reduction of nanostructure height as a function of ion exposure. C1 Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Dept Chem, Berkeley, CA 94720 USA. RP Somorjai, GA (reprint author), Univ Calif Berkeley, Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. RI Gracias, David/A-1942-2010 OI Gracias, David/0000-0003-2735-4725 NR 9 TC 72 Z9 73 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 17 PY 1998 VL 14 IS 6 BP 1458 EP 1464 DI 10.1021/la970737a PG 7 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZD421 UT WOS:000072683500027 ER PT J AU Bardotti, L Bartelt, MC Jenks, CJ Stoldt, CR Wen, JM Zhang, CM Thiel, PA Evans, JW AF Bardotti, L Bartelt, MC Jenks, CJ Stoldt, CR Wen, JM Zhang, CM Thiel, PA Evans, JW TI Formation and equilibration of submonolayer island distributions in Ag/Ag(100) homoepitaxy SO LANGMUIR LA English DT Article; Proceedings Paper CT Symposium in Honor of Brian Bent at the 213rd American-Chemical-Society National Meeting CY APR, 1997 CL SAN FRANCISCO, CALIFORNIA ID EPITAXIAL-GROWTH; BROWNIAN-MOTION; CLUSTER DIFFUSION; VACANCY CLUSTERS; AG CLUSTERS; COALESCENCE; SURFACES; SIMULATIONS; NUCLEATION; SIZE AB We present an analysis both of the nucleation and growth of two-dimensional (2D) islands or clusters during deposition of Ag on Ag(100) at 295 K and of the subsequent postdeposition equilibration of such island distributions at coverages below about 0.25 monolayer. Island formation during deposition is shown to be effectively irreversible, and the island density and size and separation distributions are characterized using a combination of scanning tunneling microscopy (STM) and high-resolution low-energy electron diffraction. Postdeposition coarsening of the adlayer is monitored via STM and is shown to be dominated typically by diffusion and subsequent coalescence of large 2D clusters rather than by Ostwald ripening. Tailored studies of such coarsening elucidate both the kinetics and the underlying cluster diffusion process. C1 Iowa State Univ, IPRT, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, IPRT, Dept Math, Ames, IA 50011 USA. Iowa State Univ, Ames Lab, Ames, IA 50011 USA. RP Thiel, PA (reprint author), Iowa State Univ, IPRT, Dept Chem, Ames, IA 50011 USA. NR 37 TC 26 Z9 27 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0743-7463 J9 LANGMUIR JI Langmuir PD MAR 17 PY 1998 VL 14 IS 6 BP 1487 EP 1492 DI 10.1021/la9707282 PG 6 WC Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary SC Chemistry; Materials Science GA ZD421 UT WOS:000072683500031 ER PT J AU Copi, CJ Olive, KA Schramm, DN AF Copi, CJ Olive, KA Schramm, DN TI Implications of a primordial origin for the dispersion in D/H in quasar absorption systems SO PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA LA English DT Article ID BIG-BANG NUCLEOSYNTHESIS; DEUTERIUM ABUNDANCE; INFLATIONARY UNIVERSE; BARYOGENESIS; DENSITY; FLUCTUATIONS; GENERATION; MECHANISM; COMPLEX; LIGHT AB We explore the difficulties with a primordial origin of variations of D/H in quasar absorption systems. In particular we examine options such as a very large-scale inhomogeneity in the baryon content of the universe. We show that very large-scale (much larger than 1 Mpc) isocurvature perturbations are excluded by current cosmic microwave background observations, Smaller-scale ad hoc perturbations (similar to 1 Mpc) still may lead to a large dispersion in primordial abundances but are subject to other constraints. C1 Univ Chicago, Ctr Astron & Astrophys, Chicago, IL 60637 USA. Case Western Reserve Univ, Cleveland, OH 44106 USA. Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA. Fermi Natl Accelerator Lab, NASA, Fermilab Astrophys Ctr, Batavia, IL 60510 USA. RP Olive, KA (reprint author), Univ Chicago, Ctr Astron & Astrophys, 5640 S Ellis Ave, Chicago, IL 60637 USA. NR 27 TC 6 Z9 6 U1 0 U2 0 PU NATL ACAD SCIENCES PI WASHINGTON PA 2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA SN 0027-8424 J9 P NATL ACAD SCI USA JI Proc. Natl. Acad. Sci. U. S. A. PD MAR 17 PY 1998 VL 95 IS 6 BP 2758 EP 2760 DI 10.1073/pnas.95.6.2758 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZC589 UT WOS:000072596200011 PM 9501162 ER PT J AU Leon, R Lobo, C Chin, TP Woodall, JM Fafard, S Ruvimov, S Liliental-Weber, Z Kalceff, MAS AF Leon, R Lobo, C Chin, TP Woodall, JM Fafard, S Ruvimov, S Liliental-Weber, Z Kalceff, MAS TI Self-forming InAs/GaP quantum dots by direct island growth SO APPLIED PHYSICS LETTERS LA English DT Article ID VISIBLE LUMINESCENCE AB InAs/GaP semiconductor quantum dots (QDs) were spontaneously formed using direct island growth (Volmer-Weber) rather than Stranski-Krastanow (S-K) growth. Structural investigations of InAs/GaP QDs suggest kinetically limited growth and show a broad size distribution Photoluminescence and cathodoluminescence spectroscopy reveal large inhomogeneous broadening with the emission peak centering at 1.7 eV, Device applications exploiting broad optical emission in QDs are discussed. (C) 1998 American Institute of Physics. C1 Australian Natl Univ, IAS, RSPhysSE, Canberra, ACT 0200, Australia. Purdue Univ, Dept Elect & Comp Engn, W Lafayette, IN 47907 USA. Natl Res Council Canada, Inst Microstruct Sci, Ottawa, ON K1A 0C6, Canada. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Technol Sydney, Microstuct Anal Unit, Broadway, NSW 2007, Australia. RP Leon, R (reprint author), Australian Natl Univ, IAS, RSPhysSE, Canberra, ACT 0200, Australia. RI Liliental-Weber, Zuzanna/H-8006-2012; Lobo, Charlene/B-3977-2013; Lobo, Charlene/G-5003-2011 OI Lobo, Charlene/0000-0002-2746-1363; Lobo, Charlene/0000-0002-2746-1363 NR 11 TC 30 Z9 30 U1 0 U2 4 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 16 PY 1998 VL 72 IS 11 BP 1356 EP 1358 DI 10.1063/1.121070 PG 3 WC Physics, Applied SC Physics GA ZC326 UT WOS:000072566000032 ER PT J AU McCartney, MR Zhu, YM AF McCartney, MR Zhu, YM TI Induction mapping of Nd2Fe14B magnetic domains by electron holography SO APPLIED PHYSICS LETTERS LA English DT Article ID ND-FE-B; WALLS AB The induction of 90 degrees magnetic domains in a Nd2Fe14B hard magnet has been mapped at high spatial resolution using off-axis electron holography. Line profiles from the reconstructed phase image established an upper limit for domain wall width of 10 nm. Thermal annealing resulted in domain wall movement, magnetization rotation, and evidence for pinning at a structural defect. (C) 1998 American Institute of Physics. C1 Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. RP McCartney, MR (reprint author), Arizona State Univ, Ctr Solid State Sci, Tempe, AZ 85287 USA. NR 20 TC 23 Z9 23 U1 1 U2 6 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 16 PY 1998 VL 72 IS 11 BP 1380 EP 1382 DI 10.1063/1.121060 PG 3 WC Physics, Applied SC Physics GA ZC326 UT WOS:000072566000040 ER PT J AU Childress, WM Crisafulli, CM Rykiel, EJ AF Childress, WM Crisafulli, CM Rykiel, EJ TI Comparison of Markovian matrix models of a primary successional plant community SO ECOLOGICAL MODELLING LA English DT Article DE Markov model; primary succession; Mount St. Helens; lupine; plant community dynamics ID DYNAMICS; VEGETATION; TRANSITION; CHAINS AB Markov matrix models have been used to simulate a variety of dynamic ecological systems such as communities and landscapes. An important question is whether time-homogeneous Markov models are adequate for successional dynamics or whether non-homogeneous models are needed to reflect changes in species composition over time. We evaluate some alternative Markov model formulations, ranging from homogeneous to semi homogeneous, to see which might be useful in replicating observed vegetation dynamics in a primary successional plant community at Mount St. Helens, Washington. We used a two-step multivariate process tt classify vegetation in 1 x 1 m quadrats in a 12 x 14 m study plot which was surveyed annually from 1983 to 1994. Four different Markov models were derived to simulate successional dynamics at the quadrat level, ranging from a completely time-homogeneous model based on quadrat class transitions pooled across all survey years, to one with annual constraints on classes allowed and with annually-adjusted transition probabilities based on these allowed classes. Although none of these models were particularly successful in replicating the observed number of vegetation classes or the number of quadrats in each class across all the survey years, the models with more annual constraints produced better results than the completely homogeneous model, The generally poor showing of these models relates primarily to annual variations in species dynamics in this community. The substantial turnover in species each year results in rapid turnover of vegetation classes, so that transitions among classes vary greatly from year to year. It appears that annual influences, both biotic and abiotic, must be implemented in the models for accurate simulations in this and probably most other primary successional communities. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Texas, Dept Biol Sci, El Paso, TX 79968 USA. US Forest Serv, Pacific NW Res Stn, Olympia, WA USA. Mt St Helens Natl Volcan Monument, Amboy, WA 98601 USA. Pacific NW Lab, Richland, WA 99352 USA. RP Childress, WM (reprint author), Univ Texas, Dept Biol Sci, El Paso, TX 79968 USA. EM childres@mail.utep.edu NR 24 TC 17 Z9 18 U1 1 U2 8 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-3800 J9 ECOL MODEL JI Ecol. Model. PD MAR 16 PY 1998 VL 107 IS 1 BP 93 EP 102 DI 10.1016/S0304-3800(97)00200-7 PG 10 WC Ecology SC Environmental Sciences & Ecology GA ZL174 UT WOS:000073406200008 ER PT J AU Nash, KL Rogers, RD Ferraro, J Zhang, J AF Nash, KL Rogers, RD Ferraro, J Zhang, J TI Lanthanide complexes with 1-hydroxyethane-1,1-diphosphonic acid: solvent organization and coordination geometry in crystalline and amorphous solids SO INORGANICA CHIMICA ACTA LA English DT Article DE crystal structures; lanthanide complexes; phosphonic acid complexes ID METHANE DIPHOSPHONIC ACIDS; CALCIUM BINDING MOLECULES; 1-HYDROXYETHYLIDENEDIPHOSPHONIC ACID; STRUCTURAL INVESTIGATIONS; DIHYDRATE; MONOHYDRATE; TETRAHYDRATE; DIFFRACTION; STABILITY; SALT AB In has been suggested in an earlier report that a 1:2 complex between europium(III) and 1-hydroxyethane-1,1-diphosphonic acid, Eu(H3HEDP)(2)(+), adopts an unexpected coordination geometry in aqueous solution. Thermodynamic and spectroscopic results were interpreted to indicate extensive hydrogen bonding within the complex, and between the complex and the water molecules in its second coordination sphere. In an attempt to confirm some of these features, samples of six amorphous and ten crystalline 1:2 complexes of selected lanthanides with HEDP have been prepared and characterized by single crystal X-ray diffraction,FT IR spectroscopy and thermogravimetric analysis, For the heavy lanthanides (To-Lu plus Y) the crystals are polymeric chains in which the metal ions are seven-coordinate, five water molecules are dispersed in interlamellar spaces, and the fifth hydrogen ion is bound to a free phosphonate oxygen on HEDP. The structure parameters for To(H3HEDP)(H2HEDP). 5H(2)O (representative of the heavy lanthanides) are a = 10.465, b = 11.415, c = 17.252 Angstrom, alpha = 90, beta = 94.22, gamma = 90 degrees and the crystal system is monoclinic. In the corresponding crystalline complexes of the light lanthanides (Eu and Nd), the metal ion is eight-coordinate and the hydration numbers are higher. The fifth hydrogen ion is not closely associated with the phosphonate group in the Eu complex but is bound in the Nd crystal. The crystal indices for [H3O][Eu(H2HEDP)(2)]. 12H(2)O are a = 10.0988, b = 11.4846, c = 11.9303 Angstrom, alpha = 99.637, beta = 91.277, gamma = 95.828 degrees. The corresponding values for Nd(H3HEDP)(H2HEDP). 7H(2)O are a = 9.318, b = 10.272, c = 11.766 Angstrom, alpha = 91.09, beta = 111.24, gamma = 98.50 degrees, Both crystallize in the triclinic crystal system. Thr amorphous analogs for both light and heavy lanthanides are more strongly hydrated (Ln(H3HEDP)(H2HEDP). 18H(2)O). FT-IR spectra confirm that there are no inner sphere water molecules in either the crystalline or amorphous solids, but the water stretching and bending frequencies are proportional to the cation radius in the amorphous species (though not in the crystalline analogs). The crystal position parameters indicate extensive hydrogen bonding between the interstitial water molecules and the bound ligands, and a hydrogen bonding interaction between the bound ligands, Though the polymeric nature of the solids is different from that in solution, the solvent organization features are consistent with the previously postulated structure of the 1:2 complex between Eu(III) and HEDP in aqueous solution. (C) 1998 Elsevier Science S.A. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. No Illinois Univ, Dept Chem, De Kalb, IL 60115 USA. RP Nash, KL (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Rogers, Robin/C-8265-2013 OI Rogers, Robin/0000-0001-9843-7494 NR 52 TC 61 Z9 61 U1 3 U2 12 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0020-1693 J9 INORG CHIM ACTA JI Inorg. Chim. Acta PD MAR 16 PY 1998 VL 269 IS 2 BP 211 EP 223 DI 10.1016/S0020-1693(97)05765-4 PG 13 WC Chemistry, Inorganic & Nuclear SC Chemistry GA YW398 UT WOS:000071931300002 ER PT J AU Brandt, A Erhan, S Kuzucu, A Lynn, D Medinnis, M Ozdes, N Schlein, PE Zeyrek, MT Zweizig, JG Cheze, JB Zsembery, J AF Brandt, A Erhan, S Kuzucu, A Lynn, D Medinnis, M Ozdes, N Schlein, PE Zeyrek, MT Zweizig, JG Cheze, JB Zsembery, J TI Measurements of single diffraction at root s=630GeV; Evidence for a non-linear alpha(t) of the pomeron SO NUCLEAR PHYSICS B LA English DT Article DE single diffraction; pomeron; pomeron trajectory; flux factor ID DEEP-INELASTIC SCATTERING; LARGE RAPIDITY GAP; CERN SPS COLLIDER; TOTAL CROSS-SECTIONS; ELASTIC-SCATTERING; PROTON DIFFRACTION; QUARK INTERACTIONS; PHOTON ENERGIES; DISSOCIATION; ISR AB We report measurements of the inclusive differential cross section for the single-diffractive reactions p(i) + (p) over bar --> p(f) + X and p + <(p)over bar (i)> --> X + <(p)over bar (f)> at root s = 630 GeV, in the momentum transfer range 0.8 < -t < 2.0 GeV2 and final-state Feynman-x(p) > 0.90. Based on the assumption of factorization, several new features of the pomeron flux factor are determined from simultaneous fits to our UA8 data and lower energy data from the CHLM collaboration at the CERN Intersecting Storage Rings. Prominent among these is that the effective pomeron Regge trajectory requires a term quadratic in t, with coefficient alpha " = 0.079 +/- 0.012 GeV-4. We also show that the data require a pomeron-proton cross section that first decreases with increasing diffractive mass (corresponding to the PPR term in the triple-Regge expansion) and then increases at larger mass (the PPP term), similar to real particle total cross sections. We measure the product K sigma(0) = 0.72+/-0.10 mb GeV-2 where K is the normalization constant of the pomeron flux factor in the proton and ao is the scale constant in the pomeron-proton total cross section. Finally, we report the occurrence of "beam jets" in the pomeron direction in the rest frame of the diffractive system. (C) 1998 Elsevier Science B.V. C1 Univ Calif Los Angeles, Los Angeles, CA 90095 USA. CENS, F-91191 Gif Sur Yvette, France. RP Brandt, A (reprint author), Fermi Natl Accelerator Lab, POB 500, Batavia, IL 60510 USA. NR 71 TC 38 Z9 38 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 16 PY 1998 VL 514 IS 1-2 BP 3 EP 44 DI 10.1016/S0550-3213(97)00813-4 PG 42 WC Physics, Particles & Fields SC Physics GA ZF723 UT WOS:000072925600001 ER PT J AU Abele, A Adomeit, J Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Beuchert, K Bischoff, S Blum, P Braune, K Bugg, DV Case, T Cramer, O Crede, V Crowe, KM Degener, T Djaoshvili, N Doser, M Dunnweber, W Ehmanns, A Engelhardt, D Faessler, MA Haddock, RP Heinsius, FH Herbstrith, A Herz, M Hessey, NP Hidas, P Hodd, C Holtzhaussen, C Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kolo, C Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H McCrady, R Meier, J Meyer, CA Montanet, L Ouared, R Peters, K Pick, B Pinder, CN Ratajczak, M Regenfus, C Resag, S Rothel, W Ryabchikov, D Sarantsev, AV Schmidt, P Scott, I Seibert, R Stock, H Strassburger, C Strohbusch, U Suffert, M Thoma, U Tischhauser, M Volcker, C Wallis, S Walther, D Wiedner, U Wittmack, K Zou, B AF Abele, A Adomeit, J Baker, CA Barnett, BM Batty, CJ Benayoun, M Berdoz, A Beuchert, K Bischoff, S Blum, P Braune, K Bugg, DV Case, T Cramer, O Crede, V Crowe, KM Degener, T Djaoshvili, N Doser, M Dunnweber, W Ehmanns, A Engelhardt, D Faessler, MA Haddock, RP Heinsius, FH Herbstrith, A Herz, M Hessey, NP Hidas, P Hodd, C Holtzhaussen, C Jamnik, D Kalinowsky, H Kammle, B Kammel, P Kisiel, J Klempt, E Koch, H Kolo, C Kunze, M Kurilla, U Lakata, M Landua, R Matthay, H McCrady, R Meier, J Meyer, CA Montanet, L Ouared, R Peters, K Pick, B Pinder, CN Ratajczak, M Regenfus, C Resag, S Rothel, W Ryabchikov, D Sarantsev, AV Schmidt, P Scott, I Seibert, R Stock, H Strassburger, C Strohbusch, U Suffert, M Thoma, U Tischhauser, M Volcker, C Wallis, S Walther, D Wiedner, U Wittmack, K Zou, B CA Crystal Barrel Collaboration TI Study of (p)over-bar-p ->eta pi(0)pi(0)pi(0) at rest SO NUCLEAR PHYSICS B LA English DT Article DE annihilation; mesons; decays ID PROTONIUM ANNIHILATION; ETA; PI; (P)OVER-BAR-P->3-PI(0); ETA-PI(0)PI(0); MESONS AB Crystal Barrel data are presented on <(p)over bar p> --> eta pi(0) pi(0) pi(0) at rest in liquid hydrogen and also in gaseous hydrogen at 12 bar. Annihilation from the initial P-3(0) state relative to P-3(2) is stronger in liquid than in gas by a factor 2.46 +/- 0.15, in fair agreement with a prediction by Batty. There is a definite peak due to eta(1440). Liquid data determine its mass as M = 1413 MeV, Gamma = 49 +/- 8 MeV. The mass is, however, lower in gas than in liquid by 12 +/- 3 MeV; we attribute this mass shift to interference with broad background amplitudes. The eta(1440) decays dominantly to eta sigma. BR[a(0)(98O)pi, a(0) --> eta pi]/BR[eta sigma] = 0.4 +/- 0.2. However, there is strong destructive interference between these two decay modes. There is also a strong, broad eta pi pi component with J(PC) = 0(-+), consistent with an earlier analysis proposing a very wide eta(1800) resonance; it contributes 31% of the eta pi(0) pi(0) pi(0) branching ratio in liquid, At the highest eta pi pi masses, there are definite 2(-+) and 1(++) signals, but we cannot establish precise resonance masses or widths. There is also evidence for the production of f(2)(1565), decaying to a(2)(1320)pi. (C) 1998 Elsevier Science B.V. C1 Univ Karlsruhe, D-76021 Karlsruhe, Germany. Univ Calif Berkeley, LBL, Berkeley, CA 94720 USA. Ruhr Univ Bochum, D-44780 Bochum, Germany. Univ Bonn, D-53115 Bonn, Germany. Hungarian Acad Sci, H-1525 Budapest, Hungary. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. CERN, CH-1211 Geneva, Switzerland. Univ Hamburg, D-22761 Hamburg, Germany. Queen Mary Univ London, London E1 4NS, England. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Munich, D-80799 Munich, Germany. LPNHE Paris 6 7, F-75252 Paris, France. Carnegie Mellon Univ, Pittsburgh, PA 15213 USA. Ctr Rech Nucl, F-67037 Strasbourg, France. RP Univ Karlsruhe, D-76021 Karlsruhe, Germany. RI Meyer, Curtis/L-3488-2014 OI Meyer, Curtis/0000-0001-7599-3973 NR 19 TC 13 Z9 13 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 EI 1873-1562 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 16 PY 1998 VL 514 IS 1-2 BP 45 EP 59 DI 10.1016/S0550-3213(97)00812-2 PG 15 WC Physics, Particles & Fields SC Physics GA ZF723 UT WOS:000072925600002 ER PT J AU Petrelli, A Cacciari, M Greco, M Maltoni, F Mangano, ML AF Petrelli, A Cacciari, M Greco, M Maltoni, F Mangano, ML TI NLO production and decay of quarkonium SO NUCLEAR PHYSICS B LA English DT Article DE heavy quarks; quarkonium; radiative corrections; hadroproduction; QCD ID COLOR-OCTET CONTRIBUTIONS; = 1.8 TEV; J/PSI-PRODUCTION; HEAVY QUARKONIUM; HADRONIC COLLISIONS; GLUON FRAGMENTATION; QCD CORRECTIONS; PSI' PRODUCTION; INELASTIC PHOTOPRODUCTION; (P)OVER-BAR-P COLLISIONS AB We present a calculation of next-to-leading order (NLO) QCD corrections to total hadronic production cross sections and to light-hadron-decay rates of heavy quarkonium states. Both colour-singlet and colour-octet contributions are included. We discuss in detail the use of covariant projectors in dimensional regularization, the structure of soft-gluon emission and the overall finiteness of radiative corrections. We compare our approach with the NLO version of the threshold expansion technique recently introduced by Braaten and Chen. Most of the results presented here are new. Others represent the first independent reevaluation of calculations already known in the literature. In this case a comparison with previous findings is reported. (C) 1998 Elsevier Science B.V. C1 Ist Nazl Fis Nucl, Pisa, Italy. DESY, D-2000 Hamburg, Germany. CERN, Div TH, CH-1211 Geneva, Switzerland. Univ Roma 3, Dipartimento Fis E Amaldi, Rome, Italy. INFN, Lab Nazl Frascati, Frascati, Italy. Univ Pisa, Dipartimento Fis, Pisa, Italy. RP Petrelli, A (reprint author), Argonne Natl Lab, Div Theory, 9700 S Cass Ave, Argonne, IL 60439 USA. EM petrelli@ibmth.difi.unipi.it; cacciari@desy.de; greco@lnf.infn.it; fabio.maltoni@cern.ch; mlm@vxcern.cern.ch NR 96 TC 175 Z9 175 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 16 PY 1998 VL 514 IS 1-2 BP 245 EP 309 DI 10.1016/S0550-3213(97)00801-8 PG 65 WC Physics, Particles & Fields SC Physics GA ZF723 UT WOS:000072925600012 ER PT J AU Cunningham, GS Hanson, KM Battle, XL AF Cunningham, GS Hanson, KM Battle, XL TI Three-dimensional reconstructions from low-count SPECT data using deformable models SO OPTICS EXPRESS LA English DT Article AB We demonstrate the reconstruction of a 3D, time-varying bolus of radiotracer from first-pass data obtained by the dynamic SPECT imager, FASTSPECT, built by the University of Arizona. The object imaged is a CardioWest Total Artificial Heart. The bolus is entirely contained in one ventricle and its associated inlet and outlet tubes. The model for the radiotracer distribution is a time-varying closed surface parameterized by 162 vertices that are connected to make 960 triangles, with uniform intensity of radiotracer inside. The total curvature of the surface is minimized through the use of a weighted prior in the Bayesian framework. MAP estimates for the vertices, interior intensity and background count level are produced for diastolic and systolic frames, the only two frames analyzed. The strength of the prior is determined by finding the corner of the L-curve. The results indicate that qualitatively pleasing results are possible even with as few as 1780 counts per time frame (total after summing over all 24 detectors). Quantitative estimates of ejection fraction and wall motion should be possible if certain restrictions in the model are removed, e.g., the spatial homogeneity of the radiotracer intensity within the volume defined by the triangulated surface, and smoothness of the surface at the tube/ventricle join. (C) 1998 Optical Society of America. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Bretagne Occidentale, Fac Med, F-29200 Brest, France. RP Cunningham, GS (reprint author), Univ Calif Los Alamos Natl Lab, MS P940, Los Alamos, NM 87545 USA. EM cunning@lanl.gov; kmh@m4next.lanl.gov; Xavier.Battle@univ-brest.fr RI Cunningham, Gregory/F-1017-2011 OI Cunningham, Gregory/0000-0001-8819-4345 NR 11 TC 30 Z9 30 U1 0 U2 0 PU OPTICAL SOC AMER PI WASHINGTON PA 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA SN 1094-4087 J9 OPT EXPRESS JI Opt. Express PD MAR 16 PY 1998 VL 2 IS 6 BP 227 EP 236 PG 10 WC Optics SC Optics GA 122NY UT WOS:000076079400003 PM 19377606 ER PT J AU Merkle, KL Bai, GR Li, Z Song, CY Thompson, LJ AF Merkle, KL Bai, GR Li, Z Song, CY Thompson, LJ TI High-resolution studies of grain boundary structure in yttria-stabilized cubic zirconia thin films grown by MOCVD SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article ID ELECTRON-MICROSCOPY; NIO; MICROSTRUCTURE AB Polycrystalline cubic-phase YSZ films with a columnar grain morphology were synthesized by MOCVD. Under suitable growth and annealing conditions highly (001) textured films were obtained and used for investigations of [001] tilt grain boundaries (GBs) by TEM, AEM and HREM. Individual primary GB dislocations in low-angle GBs were imaged by Fresnel contrast and HREM techniques. Both low and high-angle GBs were well structured at the atomic scale. No amorphous GB phases were found in any of the GBs. However, yttria segregation to GBs after high-temperature anneals was indicated by EDS. The atomic-scale structures, although in detail quite different from previously investigated oxide GBs, such as the Sigma 5, (210) GB in NiO, share a number of structural features with other oxide GBs. These include thc tendency toward coherence between low-index planes crossing the GB, misfit localization, and the formation of many types of asymmetric facets that include low-index planes. The fact that well-structured GBs free of secondary phases can be produced in YSZ is of technological importance, especially for fast-ion conduction applications, such as in high temperature fuel cells. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Merkle, KL (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 22 TC 21 Z9 21 U1 1 U2 14 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD MAR 16 PY 1998 VL 166 IS 1 BP 73 EP 89 DI 10.1002/(SICI)1521-396X(199803)166:1<73::AID-PSSA73>3.0.CO;2-B PG 17 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZG193 UT WOS:000072976500011 ER PT J AU Duscher, G Browning, ND Pennycook, SJ AF Duscher, G Browning, ND Pennycook, SJ TI Atomic column resolved electron energy-loss spectroscopy SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article ID GRAIN-BOUNDARIES; RESOLUTION; MICROSCOPE; CONTRAST; CRYSTALS AB Spatially resolved electron energy-loss spectroscopy (EELS) is rapidly developing into a unique and powerful tool to characterize internal interfaces. Because atomic column resolved Z-contrast imaging can be performed simultaneously with EELS in the scanning transmission electron microscope, this combination allows the atomic structure to be correlated with the electronic structure, and thus the local properties of interfaces or defects can be determined directly. However, the ability to characterize interfaces and defects at that level requires aot only high spatial resolution but also the exact knowledge of the beam location, from where the spectrum is obtained. Here we discuss several examples progressing from cases where the limitation in spatial resolution is given by the microscopes or the nature of the sample, to one example of impurity atoms at a grain boundary, which show intensity and fine structure changes from atomic column to atomic column. Such data can be interpreted as changes in valence of the impurity, depending on its exact site in the boundary plane. Analysis of this nature is a valuable first step in understanding the macroscopic structural, optical and electronic properties of materials. C1 Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Illinois, Chicago, IL USA. RP Duscher, G (reprint author), Oak Ridge Natl Lab, Bethel Valley Rd, Oak Ridge, TN 37831 USA. RI Duscher, Gerd/G-1730-2014; OI Duscher, Gerd/0000-0002-2039-548X; Browning, Nigel/0000-0003-0491-251X NR 30 TC 67 Z9 67 U1 0 U2 15 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD MAR 16 PY 1998 VL 166 IS 1 BP 327 EP 342 DI 10.1002/(SICI)1521-396X(199803)166:1<327::AID-PSSA327>3.0.CO;2-R PG 16 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZG193 UT WOS:000072976500027 ER PT J AU King, WE Campbell, GH AF King, WE Campbell, GH TI Quantitative comparison of HREM image intensities with image simulation for application in materials science SO PHYSICA STATUS SOLIDI A-APPLIED RESEARCH LA English DT Article ID ELECTRON-MICROSCOPY; ATOMIC-STRUCTURE; GRAIN-BOUNDARY AB Quantitive high resolution electron microscopy (QHREM) involves the detailed comparison of experimental high resolution images with image simulation based on a model and weighted by the estimated uncertainty in the experimental results. For simple metals, such as Al, models have been systematically improved using non-linear least-squares methods to obtain simulated images that are indistinguishable from experimental images within the experimental error. QHREM has also been applied to evaluate the predictions of atomistic simulations of defect structures. In this paper. we summarize the state of the art in QHREM illustrated with results from an Al grain boundary image and identify open issues to be addressed in further research. C1 Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RP King, WE (reprint author), Univ Calif Lawrence Livermore Natl Lab, Chem & Mat Sci Directorate, Livermore, CA 94550 USA. RI Campbell, Geoffrey/F-7681-2010 NR 15 TC 5 Z9 5 U1 0 U2 0 PU WILEY-V C H VERLAG GMBH PI BERLIN PA MUHLENSTRASSE 33-34, D-13187 BERLIN, GERMANY SN 0031-8965 J9 PHYS STATUS SOLIDI A JI Phys. Status Solidi A-Appl. Res. PD MAR 16 PY 1998 VL 166 IS 1 BP 343 EP 356 DI 10.1002/(SICI)1521-396X(199803)166:1<343::AID-PSSA343>3.0.CO;2-Z PG 14 WC Materials Science, Multidisciplinary; Physics, Applied; Physics, Condensed Matter SC Materials Science; Physics GA ZG193 UT WOS:000072976500028 ER PT J AU Glenn, S Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Wang, R Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartelt, J Csorna, SE Jain, V McLean, KW Marka, S Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Blis, DW Masek, G Paar, HP Prell, S Sharma, V Asner, DM Gronberg, J Hill, TS Lange, DJ Menary, S Morrison, RJ Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Ford, WT Park, H Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Crowcroft, DS Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Kim, PC Kreinick, DL Lee, T Liu, Y Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Valant-Spaight, B Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J Brandenburg, G Briere, RA Ershov, A Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, P Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Duboscq, JE Fujino, D Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Bishai, M Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M AF Glenn, S Johnson, SD Kwon, Y Roberts, S Thorndike, EH Jessop, CP Lingel, K Marsiske, H Perl, ML Savinov, V Ugolini, D Wang, R Zhou, X Coan, TE Fadeyev, V Korolkov, I Maravin, Y Narsky, I Shelkov, V Staeck, J Stroynowski, R Volobouev, I Ye, J Artuso, M Efimov, A Goldberg, M He, D Kopp, S Moneti, GC Mountain, R Schuh, S Skwarnicki, T Stone, S Viehhauser, G Xing, X Bartelt, J Csorna, SE Jain, V McLean, KW Marka, S Godang, R Kinoshita, K Lai, IC Pomianowski, P Schrenk, S Bonvicini, G Cinabro, D Greene, R Perera, LP Zhou, GJ Barish, B Chadha, M Chan, S Eigen, G Miller, JS O'Grady, C Schmidtler, M Urheim, J Weinstein, AJ Wurthwein, F Blis, DW Masek, G Paar, HP Prell, S Sharma, V Asner, DM Gronberg, J Hill, TS Lange, DJ Menary, S Morrison, RJ Nelson, HN Nelson, TK Qiao, C Richman, JD Roberts, D Ryd, A Witherell, MS Balest, R Behrens, BH Ford, WT Park, H Roy, J Smith, JG Alexander, JP Bebek, C Berger, BE Berkelman, K Bloom, K Cassel, DG Cho, HA Crowcroft, DS Dickson, M Drell, PS Ecklund, KM Ehrlich, R Foland, AD Gaidarev, P Gibbons, L Gittelman, B Gray, SW Hartill, DL Heltsley, BK Hopman, PI Kandaswamy, J Kim, PC Kreinick, DL Lee, T Liu, Y Mistry, NB Ng, CR Nordberg, E Ogg, M Patterson, JR Peterson, D Riley, D Soffer, A Valant-Spaight, B Ward, C Athanas, M Avery, P Jones, CD Lohner, M Prescott, C Yelton, J Zheng, J Brandenburg, G Briere, RA Ershov, A Gao, YS Kim, DYJ Wilson, R Yamamoto, H Browder, TE Li, Y Rodriguez, JL Bergfeld, T Eisenstein, BI Ernst, J Gladding, GE Gollin, GD Hans, RM Johnson, E Karliner, I Marsh, MA Palmer, M Selen, M Thaler, JJ Edwards, KW Bellerive, A Janicek, R MacFarlane, DB Patel, PM Sadoff, AJ Ammar, R Baringer, P Bean, A Besson, D Coppage, D Darling, C Davis, P Hancock, N Kotov, S Kravchenko, I Kwak, N Anderson, S Kubota, Y Lee, SJ O'Neill, JJ Patton, S Poling, R Riehle, T Smith, A Alam, MS Athar, SB Ling, Z Mahmood, AH Severini, H Timm, S Wappler, F Anastassov, A Duboscq, JE Fujino, D Gan, KK Hart, T Honscheid, K Kagan, H Kass, R Lee, J Spencer, MB Sung, M Undrus, A Wanke, R Wolf, A Zoeller, MM Nemati, B Richichi, SJ Ross, WR Skubic, P Bishai, M Fast, J Hinson, JW Menon, N Miller, DH Shibata, EI Shipsey, IPJ Yurko, M TI Search for inclusive b -> sl(+)l(-) SO PHYSICAL REVIEW LETTERS LA English DT Article ID B-MESON DECAYS; RESONANCE CONTRIBUTIONS; B->SL+L; B->K(ASTERISK)L(+)L(-); GENERATION; B->S-GAMMA; ASYMMETRY; DISTANCE; PHYSICS; QUARK AB We have searched for the effective flavor changing neutral-current decays b --> sl+l(-) using an inclusive method. We set upper limits on the branching ratios B(b --> se(+)e(-)) < 5.7 x 10(-5), B(b --> s mu(+)mu(-)) < 5.8 x 10(-5), and B(b --> se(+/-)mu(-/+)) < 2.2 x 10(-5) [at 90% confidence level(C.L.)]. Combing the dielectron and dimuon decay modes we find B(b --> sl(+)l(-)) < 4.2 x 10(-5) (at 90% C.L.). C1 Univ Rochester, Rochester, NY 14627 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. So Methodist Univ, Dallas, TX 75275 USA. Syracuse Univ, Syracuse, NY 13244 USA. Vanderbilt Univ, Nashville, TN 37235 USA. Virginia Polytech Inst & State Univ, Blacksburg, VA 24061 USA. Wayne State Univ, Detroit, MI 48202 USA. CALTECH, Pasadena, CA 91125 USA. Univ Calif San Diego, La Jolla, CA 92093 USA. Univ Calif Santa Barbara, Santa Barbara, CA 93106 USA. Univ Colorado, Colorado Springs, CO 80309 USA. Cornell Univ, Ithaca, NY 14853 USA. Univ Florida, Gainesville, FL 32611 USA. Harvard Univ, Cambridge, MA 02138 USA. Univ Hawaii Manoa, Honolulu, HI 96822 USA. Univ Illinois, Champaign, IL 61801 USA. Carleton Univ, Ottawa, ON K1S 5B6, Canada. Inst Particle Phys, Ottawa, ON, Canada. McGill Univ, Montreal, PQ H3A 2T8, Canada. Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Ithaca Coll, Ithaca, NY 14850 USA. Univ Kansas, Lawrence, KS 66045 USA. Univ Minnesota, Minneapolis, MN 55455 USA. SUNY Albany, Albany, NY 12222 USA. Ohio State Univ, Columbus, OH 43210 USA. Univ Oklahoma, Norman, OK 73019 USA. Purdue Univ, W Lafayette, IN 47907 USA. Yonsei Univ, Seoul 120749, South Korea. Brookhaven Natl Lab, Upton, NY 11973 USA. Univ Texas, Austin, TX 78712 USA. Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. BINP, RU-630090 Novosibirsk, Russia. RP Univ Rochester, 601 Elmwood Ave, Rochester, NY 14627 USA. RI Briere, Roy/N-7819-2014; OI Briere, Roy/0000-0001-5229-1039; Bean, Alice/0000-0001-5967-8674 NR 28 TC 51 Z9 51 U1 2 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2289 EP 2293 DI 10.1103/PhysRevLett.80.2289 PG 5 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700009 ER PT J AU Macek, JH Ovchinnikov, SY AF Macek, JH Ovchinnikov, SY TI Theory of rapidly oscillating electron angular distributions in slow ion-atom collisions SO PHYSICAL REVIEW LETTERS LA English DT Article ID IONIZATION; HE AB A general expression for the ionization amplitude in slow ion-atom collisions is derived. The expression is inverted to obtain adiabatic electronic wave functions at complex values of the internuclear distance. It is shown that beating between sigma and pi components of electronic wave functions gives rise to rapid oscillations of electron angular distributions with ion velocity nu. These rapid oscillations measure the real part of that eigenvalue whose imaginary part gives the well-known Wannier exponent. C1 Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RP Macek, JH (reprint author), Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. RI Ovchinnikov, Serguei/C-4994-2014 NR 9 TC 47 Z9 47 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2298 EP 2301 DI 10.1103/PhysRevLett.80.2298 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700011 ER PT J AU Jeon, D Ball, M Budnick, J Chu, CM Ellison, M Hamilton, B Kang, X Kiang, LL Lee, SY Ng, KY Pei, A Riabko, A Sloan, T Syphers, M AF Jeon, D Ball, M Budnick, J Chu, CM Ellison, M Hamilton, B Kang, X Kiang, LL Lee, SY Ng, KY Pei, A Riabko, A Sloan, T Syphers, M TI A mechanism of anomalous diffusion in particle beams SO PHYSICAL REVIEW LETTERS LA English DT Article ID RF VOLTAGE MODULATION; SYNCHROTRON MOTION; RESONANCE ISLANDS; SYSTEM AB Experimental observation of particle diffusion mechanism in the presence of overlapping parametric resonances generated by a time dependent rf phase modulation is analyzed. We find that the regime of fast emittance growth is associated with the rapid particle motion along the separatrix of a dominant parametric resonance, the slow growth regime is related to particle diffusion in the chaotic sea, and the emittance saturation occurs when beam particles fill the chaotic region bounded by an invariant torus. Experimental data observed at the Indiana University Cyclotron Facility (IUCF) Cooler Ring are shown to agree well with the theoretical analysis. C1 Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. Fermilab, Batavia, IL 60510 USA. Brookhaven Natl Lab, AGS Dept, Upton, NY 11973 USA. RP Jeon, D (reprint author), Indiana Univ, Dept Phys, Bloomington, IN 47405 USA. RI Jeon, Dong-O/S-2137-2016 OI Jeon, Dong-O/0000-0001-6482-5878 NR 17 TC 10 Z9 10 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2314 EP 2317 DI 10.1103/PhysRevLett.80.2314 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700015 ER PT J AU Huang, ZR Ruth, RD AF Huang, ZR Ruth, RD TI Effects of focusing on radiation damping and quantum excitation in electron storage rings SO PHYSICAL REVIEW LETTERS LA English DT Article AB In this Letter we calculate the effects of a linearly varying focusing field on radiation damping and quantum excitation in an electron storage ring using a quantum mechanical perturbation approach. This model predicts correctly the limits of pure bending and pure focusing. We find that quantum excitation can be exponentially suppressed by the focusing field when the radiation formation length is comparable to the transverse-oscillation wavelength. This new result on quantum excitation may have interesting applications in the generation of ultralow emittance beams. C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Huang, ZR (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 6 TC 7 Z9 7 U1 0 U2 0 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2318 EP 2321 DI 10.1103/PhysRevLett.80.2318 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700016 ER PT J AU Afeyan, BB Chou, AE Matte, JP Town, RPJ Kruer, WJ AF Afeyan, BB Chou, AE Matte, JP Town, RPJ Kruer, WJ TI Kinetic theory of electron-plasma and ion-acoustic waves in nonuniformly heated laser plasmas SO PHYSICAL REVIEW LETTERS LA English DT Article ID STIMULATED RAMAN-SCATTERING; TRANSPORT; DISTRIBUTIONS AB Using Fokker-Planck simulations, we have studied the evolution of different charge state plasmas heated by lasers having transverse spatial modulations (speckle patterns) and hot spots. The kinetic response of the plasma is computed using the resulting strongly non-Maxwellian electron velocity distribution functions. Significant reductions in the electron plasma wave Landau damping rates and large modulations in the local ion acoustic frequencies are found which impact the behavior of all parametric instabilities in such plasmas. Various experimental consequences are given. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. INRS Energie Mat, Varennes, PQ J0L 2P0, Canada. Univ Rochester, Laser Energet Lab, Rochester, NY 14623 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. RP Afeyan, BB (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. NR 28 TC 49 Z9 49 U1 1 U2 8 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2322 EP 2325 DI 10.1103/PhysRevLett.80.2322 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700017 ER PT J AU Lee, JH Peebles, WA Jaeger, EF Doyle, EJ Luhmann, NC Petty, CC Pinsker, RI Prater, R Rhodes, TL AF Lee, JH Peebles, WA Jaeger, EF Doyle, EJ Luhmann, NC Petty, CC Pinsker, RI Prater, R Rhodes, TL TI Internal electric field structure of launched fast magnetosonic waves in the DIII-D tokamak SO PHYSICAL REVIEW LETTERS LA English DT Article ID CURRENT DRIVE; IMPROVED CONFINEMENT; HIGH-BETA; MODE; STABILITY; PLASMAS AB Results are obtained, for the first time in a major tokamak plasma, of the spatial electric field structure of a launched fast magnetosonic wave (FW). The FW launch directionality necessary for current drive has been confirmed at a position close to the FW antenna. The FW electric field profile is determined using X-mode reflectometry. Electric field profiles, calculated using a full-wave numerical code, exhibit many features common to the experimental results. However, differences remain regarding density dependence that suggest alternative damping mechanisms may exist. C1 Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. Univ Calif Los Angeles, Inst Plasma & Fus Res, Los Angeles, CA 90095 USA. Hongik Univ, Sch Elect & Elect Engn, Seoul 121791, South Korea. Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. Univ Calif Davis, Dept Appl Sci, Davis, CA 95616 USA. Gen Atom Co, San Diego, CA 92186 USA. RP Lee, JH (reprint author), Univ Calif Los Angeles, Dept Elect Engn, Los Angeles, CA 90095 USA. NR 21 TC 8 Z9 8 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2330 EP 2333 DI 10.1103/PhysRevLett.80.2330 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700019 ER PT J AU Wong, KL Springer, PT Hammer, JH Iglesias, CA Osterheld, AL Foord, ME Bruns, HC Emig, JA Deeney, C AF Wong, KL Springer, PT Hammer, JH Iglesias, CA Osterheld, AL Foord, ME Bruns, HC Emig, JA Deeney, C TI Spectroscopic characterization of an argon-neon Z-pinch plasma at stagnation SO PHYSICAL REVIEW LETTERS LA English DT Article ID PUFF Z-PINCH; TIME AB The density, temperature, and radiation coupling are investigated in strongly radiating Ar-Ne Z-pinch plasmas at stagnation using a novel high resolution space-and time-resolving x-ray spectrometer. One- and two-dimensional electron temperature profiles are obtained from the slope of the Ne recombination continuum. The electron density and ion temperature are determined from comparisons of the heliumlike Ar Rydberg series with detailed line-profile calculations. 2D nonlocal thermodynamic equilibrium calculations predict a radiating region denser and cooler than measured. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Wong, KL (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. NR 19 TC 40 Z9 40 U1 1 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2334 EP 2337 DI 10.1103/PhysRevLett.80.2334 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700020 ER PT J AU Donati, C Douglas, JF Kob, W Plimpton, SJ Poole, PH Glotzer, SC AF Donati, C Douglas, JF Kob, W Plimpton, SJ Poole, PH Glotzer, SC TI Stringlike cooperative motion in a supercooled liquid SO PHYSICAL REVIEW LETTERS LA English DT Article ID LENNARD-JONES MIXTURE; MODE-COUPLING THEORY; SOFT-SPHERE ALLOYS; GLASS-TRANSITION; STRUCTURAL RELAXATION; MULTIDIMENSIONAL NMR; MOLECULAR-DYNAMICS; BETA-RELAXATION; LIVING POLYMERS; O-TERPHENYL AB Extensive molecular dynamics simulations are performed on a glass-forming Lennard-Jones mixture to determine the nature of the cooperative motions occurring in this model fragile liquid. We observe stringlike cooperative molecular motion ("strings") at temperatures well above the glass transition. The mean length of the strings increases upon cooling, and the string length distribution is found to be nearly exponential. C1 NIST, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. NIST, Div Polymers, Gaithersburg, MD 20899 USA. Johannes Gutenberg Univ Mainz, Inst Phys, D-55099 Mainz, Germany. Sandia Natl Labs, Parallel Computat Sci Dept, Albuquerque, NM 87185 USA. Univ Western Ontario, Dept Appl Math, London, ON N6A 5B7, Canada. RP Glotzer, SC (reprint author), NIST, Ctr Theoret & Computat Mat Sci, Gaithersburg, MD 20899 USA. EM sharon.glotzer@nist.gov RI Poole, Peter/C-7943-2009; Donati, Claudio/J-5180-2012; Kob, Walter/L-7010-2013; OI Poole, Peter/0000-0001-5985-0585; Kob, Walter/0000-0001-7405-2178; Donati, Claudio/0000-0001-8688-1651 NR 50 TC 640 Z9 642 U1 2 U2 78 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2338 EP 2341 DI 10.1103/PhysRevLett.80.2338 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700021 ER PT J AU Wang, RH Zhu, YM Shapiro, SM AF Wang, RH Zhu, YM Shapiro, SM TI Structural defects and the origin of the second length scale in SrTiO3 SO PHYSICAL REVIEW LETTERS LA English DT Article ID X-RAY-SCATTERING; CRITICAL FLUCTUATIONS; NEUTRON-SCATTERING; CENTRAL PEAK AB To understand the origin of the second long-length scale in SrTiO3, we studied structural defects in Verneuil-grown single crystals by transmission electron microscopy. The density of the dislocations was observed to decrease with increasing depth from the original cut surface of the crystals. The high density of dislocations in the skin region is most likely responsible for the second length scale. C1 Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Wang, RH (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Upton, NY 11973 USA. NR 21 TC 66 Z9 66 U1 0 U2 24 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2370 EP 2373 DI 10.1103/PhysRevLett.80.2370 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700029 ER PT J AU Medarde, M Lacorre, P Conder, K Fauth, F Furrer, A AF Medarde, M Lacorre, P Conder, K Fauth, F Furrer, A TI Giant O-16-O-18 isotope effect on the metal-insulator transition of RNiO3 perovskites (R equals rare earth) SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELECTRONIC-STRUCTURE; CRYSTAL-STRUCTURE; PRNIO3; NDNIO3; SPECTROSCOPY; DIFFRACTION; TEMPERATURE; GAP; ND AB The observation of unusually large, positive and rare-earth dependent O-16-O-18 isotope shifts in the metal-insulator transition temperature T-MI Of RNIO3 perovskites is reported (Delta T-MI less than or equal to +10.3 K). The results clearly indicate that the mechanism of the transition involves a strong electron-lattice interaction. A simple model based on the existence of Jahn-Teller polarons in a stoichiometric, metallic, charge-transfer system is used to account for the evolution of Delta T-MI along the series. C1 Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France. ETH Zurich, Neutron Scattering Lab, CH-5232 Villigen, Switzerland. Paul Scherrer Inst, CH-5232 Villigen, Switzerland. Univ Maine, UPRESA CNRS 6010, Lab Fluorures, F-72085 Le Mans 9, France. ETH Zurich, Festkorperphys Lab, CH-8093 Zurich, Switzerland. RP Medarde, M (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Fauth, Francois/K-9643-2014 OI Fauth, Francois/0000-0001-9465-3106 NR 26 TC 103 Z9 103 U1 3 U2 19 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2397 EP 2400 DI 10.1103/PhysRevLett.80.2397 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700036 ER PT J AU Ganichev, SD Ziemann, E Gleim, T Prettl, W Yassievich, IN Perel, VI Wilke, I Haller, EE AF Ganichev, SD Ziemann, E Gleim, T Prettl, W Yassievich, IN Perel, VI Wilke, I Haller, EE TI Carrier tunneling in high-frequency electric fields SO PHYSICAL REVIEW LETTERS LA English DT Article ID FAR-INFRARED RADIATION; DEEP IMPURITIES; IONIZATION; TIME AB An enhancement of tunnel ionization of deep impurities in semiconductors in an alternating held as compared to static fields has been observed. The transition between the quasistatic and the high-frequency regime is determined by the tunneling time. For the case of deep impurities this is the time of redistribution of the defect vibrational system which depends strongly on temperature and the impurity structure. A theory of tunnel ionization of deep impurities by high-frequency fields has been developed. C1 Univ Regensburg, Inst Expt & Angew Phys, D-93040 Regensburg, Germany. Russian Acad Sci, AF Ioffe Physicotech Inst, St Petersburg 194021, Russia. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Ganichev, SD (reprint author), Univ Regensburg, Inst Expt & Angew Phys, D-93040 Regensburg, Germany. NR 14 TC 40 Z9 40 U1 0 U2 5 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2409 EP 2412 DI 10.1103/PhysRevLett.80.2409 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700039 ER PT J AU Smith, DL Lee, EY Narayanamurti, V AF Smith, DL Lee, EY Narayanamurti, V TI Ballistic electron emission microscopy for nonepitaxial metal/semiconductor interfaces SO PHYSICAL REVIEW LETTERS LA English DT Article ID ELASTIC-SCATTERING; TRANSPORT AB We present a model of ballistic electron emission microscopy (BEEM) that includes elastic scattering at nonepitaxial metal/semiconductor interfaces. In the weak scattering limit, the model reduces to the traditional description of BEEM. In the strong scattering limit, the model quantitatively describes (1) the relative magnitudes of BEEM currents into the Gamma, L, and X channels for Au/GaAs(100); (2) the relative magnitudes of the currents for Au/Si(100) and -(111); (3) the relative magnitudes of currents for Au/GaAs and Au/Si; and (4) the absolute magnitudes of the currents for these materials. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Calif Santa Barbara, Dept Elect & Comp Engn, Santa Barbara, CA 93106 USA. RP Smith, DL (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 16 TC 47 Z9 47 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2433 EP 2436 DI 10.1103/PhysRevLett.80.2433 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700045 ER PT J AU Yarmoff, JA Liu, TD Qiu, SR Sroubek, Z AF Yarmoff, JA Liu, TD Qiu, SR Sroubek, Z TI Mechanism of electron emission from Al(100) bombarded by slow Li+ ions SO PHYSICAL REVIEW LETTERS LA English DT Article ID COLLISIONS; METALS; SOLIDS AB Emission of electrons from Al(100) during bombardment by 50-520 eV Li+ ions was measured as a function of incident ion energy and direction. The process was modeled by a surface electron-hole pair excitation mechanism and was quantified with a one-electron parametric theory. This is a previously unidentified mechanism which is characterized by a strong dependence on the energy and angle of incidence of the primary particle. Good agreement between the experimental data and theory is found, which indicates that this mechanism is indeed responsible for electron emission during Li-Ai collisions. C1 Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Acad Sci Czech Republ, Inst Radio Engn & Elect, CR-18251 Prague, Czech Republic. RP Yarmoff, JA (reprint author), Univ Calif Riverside, Dept Phys, Riverside, CA 92521 USA. NR 14 TC 14 Z9 14 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 16 PY 1998 VL 80 IS 11 BP 2469 EP 2472 DI 10.1103/PhysRevLett.80.2469 PG 4 WC Physics, Multidisciplinary SC Physics GA ZC385 UT WOS:000072572700054 ER PT J AU Bohn, AA Forsyth, CS Stoner, GD Reed, DJ Frank, AA AF Bohn, AA Forsyth, CS Stoner, GD Reed, DJ Frank, AA TI Effect of cocaine, 95% oxygen and ellagic acid on the development and antioxidant status of cultured rat embryos SO TOXICOLOGY LETTERS LA English DT Article DE cocaine; oxygen; ellagic acid; antioxidant status; cultured rat embryos ID ISCHEMIA REPERFUSION; VASCULAR DISRUPTION; DEVELOPMENT INVITRO; PREGNANCY; EXPOSURE; MICE; TERATOGENICITY; TOXICITY; CHILD AB Prenatal exposure to cocaine has been associated with adverse developmental effects and current data suggest cocaine induced malformations are caused by ischemic-reperfusion injury. This study was undertaken to assess a new in vitro model which uses a routine rat whole embryo culture system that incorporates a change in oxygen status, and to examine the effects of altered oxygen status and pretreatment with ellagic acid (EA), an anti-oxidant, after cocaine exposure. Embryos were evaluated by determining a developmental score and by measuring tissue reduced glutathione (GSH) levels. Following re-oxygenation with 95% O-2 for the last 6 h of culture, embryos treated with cocaine had reduced developmental scores and GSH levels. Embryos treated with cocaine and not re-oxygenated with 95% O-2 did not have reduced developmental scores. EA blocked the effects of cocaine on developmental score and GSH level. These data support ischemia-reperfusion injury as the mechanism of cocaine developmental toxicity. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. C1 Colorado State Univ, Dept Pathol, Ft Collins, CO 80523 USA. Oak Ridge Natl Lab, Oak Ridge, TN 37830 USA. Ohio State Univ, Dept Prevent Med, Columbus, OH 43210 USA. Oregon State Univ, Dept Biochem & Biophys, Corvallis, OR 97331 USA. RP Frank, AA (reprint author), Colorado State Univ, Dept Pathol, Ft Collins, CO 80523 USA. EM tfrank@lamar.colostate.edu RI Bohn, Andrea/E-1682-2017 OI Bohn, Andrea/0000-0001-9589-8455 FU NIDA NIH HHS [5 F32 DA055900] NR 33 TC 8 Z9 8 U1 1 U2 1 PU ELSEVIER SCI IRELAND LTD PI CLARE PA CUSTOMER RELATIONS MANAGER, BAY 15, SHANNON INDUSTRIAL ESTATE CO, CLARE, IRELAND SN 0378-4274 J9 TOXICOL LETT JI Toxicol. Lett. PD MAR 16 PY 1998 VL 95 IS 1 BP 15 EP 21 DI 10.1016/S0378-4274(98)00010-1 PG 7 WC Toxicology SC Toxicology GA ZU548 UT WOS:000074209100003 PM 9650642 ER PT J AU Geiser, U Williams, JM AF Geiser, U Williams, JM TI Bis(tetra-n-butylammonium) hexa-mu(3)-sulfido-hexakis(nitrosoiron) SO ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS LA English DT Article ID CLUSTERS AB The title compound, [N(C4H9)(4)](2)[Fe6S6(NO)(6)], is the second salt of the unusual cyclic anion [Fe6S6(NO)(6)](2-). The anion consists of two used Fe3S3 rings, with terminal nitrosyl groups bound to the Fe atoms. C1 Argonne Natl Lab, Div Chem, Argonne, IL 60439 USA. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. RP Geiser, U (reprint author), Argonne Natl Lab, Div Chem, 9700 S Cass Ave, Argonne, IL 60439 USA. NR 6 TC 4 Z9 4 U1 0 U2 0 PU MUNKSGAARD INT PUBL LTD PI COPENHAGEN PA 35 NORRE SOGADE, PO BOX 2148, DK-1016 COPENHAGEN, DENMARK SN 0108-2701 J9 ACTA CRYSTALLOGR C JI Acta Crystallogr. Sect. C-Cryst. Struct. Commun. PD MAR 15 PY 1998 VL 54 BP 292 EP 293 DI 10.1107/S0108270197013802 PN 3 PG 2 WC Chemistry, Multidisciplinary; Crystallography SC Chemistry; Crystallography GA ZF121 UT WOS:000072864700005 ER PT J AU Cheng, J Waters, LC Fortina, P Hvichia, G Jacobson, SC Ramsey, JM Kricka, LJ Wilding, P AF Cheng, J Waters, LC Fortina, P Hvichia, G Jacobson, SC Ramsey, JM Kricka, LJ Wilding, P TI Degenerate oligonucleotide primed polymerase chain reaction and capillary electrophoretic analysis of human DNA on microchip-based devices SO ANALYTICAL BIOCHEMISTRY LA English DT Article DE whole human genome amplification; degenerate oligonucleotide primer; dystrophin gene; chip PCR; microchip electrophoresis ID WHOLE GENOME AMPLIFICATION; SILICON-GLASS CHIPS; PCR AMPLIFICATION; ARRAYS; PERFORMANCE; TECHNOLOGY; SYSTEMS; CELL AB Random amplification of the human genome using the degenerate oligonucleotide primed-polymerase chain reaction (DOP-PCR) was performed in a silicon-glass chip. An aliquot of the DOP-PCR amplified genomic DNA was then introduced into another silicon-glass chip for a locus-specific, multiplex PCR of the dystrophin gene exons in order to detect deletions causing Duchenne/Becker muscular dystrophy, Amplicons were analyzed by both conventional capillary electrophoresis and microchip electrophoresis and results were compared to those obtained using standard non-chip-based PCR assays, Results from microchip electrophoresis were consistent with those from conventional capillary electrophoresis. Whole genome amplification products obtained by DOP-PCR proved to be a suitable template for multiplex PCR as long as amplicon size was <250 bp. Successful detection and resolution of all PCR products from the multiplex PCR clearly shows the feasibility of performing complex PCR assays using microfabricated devices. (C) 81998 Academic Press. C1 Univ Penn, Sch Med, Dept Pathol & Lab Med, Philadelphia, PA 19104 USA. Univ Penn, Sch Med, Childrens Hosp Philadelphia, Dept Pediat, Philadelphia, PA 19104 USA. Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Univ Penn, Dept Pathol, Philadelphia, PA 19104 USA. Univ Penn, Dept Lab Med, Philadelphia, PA 19104 USA. RP Kricka, LJ (reprint author), Univ Penn, Sch Med, Dept Pathol & Lab Med, 3400 Spruce St, Philadelphia, PA 19104 USA. EM larry_kricka@path1a.med.upenn.edu NR 38 TC 102 Z9 118 U1 1 U2 8 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0003-2697 J9 ANAL BIOCHEM JI Anal. Biochem. PD MAR 15 PY 1998 VL 257 IS 2 BP 101 EP 106 DI 10.1006/abio.1997.2531 PG 6 WC Biochemical Research Methods; Biochemistry & Molecular Biology; Chemistry, Analytical SC Biochemistry & Molecular Biology; Chemistry GA ZC937 UT WOS:000072634000002 PM 9514777 ER PT J AU Pretty, JR Duckworth, DC Van Berkel, GJ AF Pretty, JR Duckworth, DC Van Berkel, GJ TI Electrochemical sample pretreatment coupled on-line with ICP-MS: Analysis of uranium using an anodically conditioned glassy carbon working electrode SO ANALYTICAL CHEMISTRY LA English DT Article ID PLASMA-MASS-SPECTROMETRY; VOLTAMMETRY FLOW CELL; ATOMIC EMISSION-SPECTROMETRY; STRIPPING VOLTAMMETRY; TRACE URANIUM; ONLINE AB Uranium may be accumulated at an anodized glassy carbon (GC) electrode at -0.15 V and stripped at +1.15 V, allowing electrochemical preconcentration and matrix elimination on-line with ICP-MS detection. Analyte levels ranging from 20 mu g/L to subnanogram per liter were determined in matrix-free standards with good linearity and precision. Detection limits (3s(y/x)/slope) determined from standard addition plots were 0.12 ng/L with 10-min accumulation time, permitting the minor isotopes of uranium to be determined with good precision at total uranium concentrations as low as 5.0 mu g/L. High levels of salt matrix moderately suppressed uranium deposition efficiency, and therefore stripping peak height, but could be compensated for by extended accumulation times. Matrix elimination of up to 20 000 mg/L Na was complete with just a 90-s cell washout time. Uranium was quantified in a certified seawater matrix, NASS-4 (certified uranium level-2.68 +/- 0.12 mu g/L), at several levels of dilution: recoveries ranged from 100.4 to 119.4% and all agreed with the true value within 95% CL. Thorium showed a similar affinity for anodized GC, and simultaneous measurement of thorium and uranium was demonstrated. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP Van Berkel, GJ (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. EM vanberkelgj@ornl.gov RI Duckworth, Douglas/B-7171-2015 OI Duckworth, Douglas/0000-0002-8161-5685 NR 33 TC 31 Z9 31 U1 0 U2 13 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 15 PY 1998 VL 70 IS 6 BP 1141 EP 1148 DI 10.1021/ac971082l PG 8 WC Chemistry, Analytical SC Chemistry GA ZC318 UT WOS:000072565200013 ER PT J AU McLuckey, SA Stephenson, JL Asano, KG AF McLuckey, SA Stephenson, JL Asano, KG TI Ion/ion proton-transfer kinetics: Implications for analysis of ions derived from electrospray of protein mixtures SO ANALYTICAL CHEMISTRY LA English DT Article ID TRAP MASS-SPECTROMETRY; IONIZATION; DECONVOLUTION; PRINCIPLES; SPECTRA AB Protein ions of different mass and charge but similar mass-to-charge ratios are shown to undergo significantly different rates of differential neutralization, defined as the rate of change of charge with time, upon initiation of reactions with oppositely charged ions in the quadrupole ion trap, Overlapping charge state distributions arising from mixtures of ions of dissimilar charge are separated on the mass-to-charge scale at short reactions times. It is also demonstrated that the time frame for near total neutralization, defined as charge reduction to the 1+ ion, is relatively insensitive to initial charge state, It is shown, for example, that the (M + 11H)(11+)-(M + 22H)(22+)l ions derived from horse skeletal muscle apomyoglobin yield the (M + H)(+) ion as the major ion/ion reaction product over the same reaction period that largely converts doubly protonated bradykinin to the singly protonated species, Less than 25% of the bradykinin ions are expected to be totally neutralized when roughly 7% of the myoglobin ions are expected to be totally neutralized, The phenomenon of significantly different initial differential neutralization rates for ions of dissimilar charge, and the relative insensitivity to ion charge for total neutralization, can be used to advantage in strategies for protein ion mixture analysis. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RP McLuckey, SA (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. RI Stephenson, James/A-9262-2009; McLuckey, Scott/B-2203-2009; Asano, Keiji/L-3164-2016 OI McLuckey, Scott/0000-0002-1648-5570; Asano, Keiji/0000-0003-2254-3586 FU NIGMS NIH HHS [R01GM45372] NR 17 TC 66 Z9 66 U1 0 U2 8 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 15 PY 1998 VL 70 IS 6 BP 1198 EP 1202 DI 10.1021/ac9710137 PG 5 WC Chemistry, Analytical SC Chemistry GA ZC318 UT WOS:000072565200022 PM 9530009 ER PT J AU Wunschel, DS Muddiman, DC Fox, KF Fox, A Smith, RD AF Wunschel, DS Muddiman, DC Fox, KF Fox, A Smith, RD TI Heterogeneity in Bacillus cereus PCR products detected by ESI-FTICR mass spectrometry SO ANALYTICAL CHEMISTRY LA English DT Article ID ASSISTED LASER-DESORPTION; RIBOSOMAL-RNA; ION ACCUMULATION; ELECTROSPRAY; MATRIX; DNA; SEQUENCES; 16S; POLYMORPHISMS; SUBTILIS AB PCR amplification of a segment of the 16/23S rDNA interspace region (ISR) from Bacillus cereus 6464 produced a mixture of products. An 89-bp product was predicted on the basis of the reported sequence. The ESI-FTICR analysis revealed three double-stranded products, differing in size by a single nucleotide corresponding to two homoduplexes of 89 and 88 base pairs and a heteroduplex of 89 and 88 nucleotide-strands. These were produced from a single preparation of genomic DNA and a single primer pair. ESI-FTICR analysis of the single strands identified a deletion of a T in the coding strand and a corresponding loss of an A in the noncoding strand of this product. The ESI-FTICR analysis indicated the presence of an unreported sequence variation between rRNA operons in this organism. This report illustrates that PCR products amplified from templates differing by a single nucleotide can be resolved and identified using ESI-FTICR at the 89-bp level. Furthermore, the ESI-FTICR mass measurements provided the identity of the deletion, which is indicative of interoperon variability. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. Univ S Carolina, Sch Med, Dept Microbiol & Immunol, Columbia, SC 29209 USA. RP Smith, RD (reprint author), Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. EM dcmuddim@vcu.edu; Dick.Smith@pnl.gov RI Wunschel, David/F-3820-2010; Smith, Richard/J-3664-2012 OI Smith, Richard/0000-0002-2381-2349 NR 28 TC 26 Z9 26 U1 0 U2 2 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0003-2700 J9 ANAL CHEM JI Anal. Chem. PD MAR 15 PY 1998 VL 70 IS 6 BP 1203 EP 1207 DI 10.1021/ac971156t PG 5 WC Chemistry, Analytical SC Chemistry GA ZC318 UT WOS:000072565200023 PM 9530010 ER PT J AU LaRue, KEA Bradbury, EM Freyer, JP AF LaRue, KEA Bradbury, EM Freyer, JP TI Differential regulation of cyclin-dependent kinase inhibitors in monolayer and spheroid cultures of tumorigenic and nontumorigenic fibroblasts SO CANCER RESEARCH LA English DT Article ID CELL-CYCLE; MULTICELLULAR SPHEROIDS; METABOLIC ALTERATIONS; GROWTH; PROTEIN; TRANSFORMATION; PROGRESSION; APOPTOSIS; ANCHORAGE; POINTS AB The Ras proto-oncogene has been implicated in the in vivo development of tumors and in the in vitro transformation of cultured cell lines. In both of these conditions, Ras-mediated disruption of cell cycle-regulatory mechanisms leads to unregulated cellular proliferation, although the exact mechanisms hy which Ras accomplishes this are not clear. Using as a model the M1 and MR1 rat fibroblast cell lines, which differ in the expression of a regulated Ras (M1 cells) versus a constitutively active Ras (MR1 cells), we examined the role of Ras in the control of cellular proliferation in two-dimensional (monolayer) and three-dimensional (spheroid) cell cultures. These cell lines are very similar in their monolayer growth characteristics, but M1 cells will arrest their cell cycle progression in aggregate culture, whereas MR1 cells proliferate normally as small spheroids. We report here that G(1)-phase arrest in plateau-phase monolayer cultures of both M1 and MRI cells correlates with up-regulated expression of the cyclin-dependent kinase (CDK) inhibitor p18(INK4C). Enhanced p18(INK4c) expression was also observed in G(1)-arrested M1 cells cultured as multicellular spheroids but was not induced in small proliferating MRI multicellular spheroids. The kinetics of G(1) arrest in M1 cells after inoculation into aggregate culture correlated well with the induction of p18(INK4c) expression. Conversely, resumption of proliferation in monolayer culture of arrested M1 cells isolated from spheroids coincided with the loss of expression of p18(INK4c). After extended culture, cells in the inner region of MR1 spheroids arrested in the G(1) phase without any up-regulation of p18(INK4c) expression. In this case, the CDK inhibitor p21(Cip1/Waf1) was selectively induced in the inner regions of large MR1 spheroids, concomitant with a decrease in cyclin and CDK expression. Thus, Ras-dependent regulation of p18(INK4c) expression seems to control the ability of rat embryo fibroblasts to proliferate as small multicellular aggregates, whereas p21(Cip1Waf1) expression seems to regulate the G(1)-phase arrest induced by the stressful microenvironment found within the inner region of large spheroids. C1 Univ Calif Los Alamos Natl Lab, Div Life Sci, Cellular & Mol Biol Grp, Los Alamos, NM 87545 USA. RP LaRue, KEA (reprint author), Univ Calif Los Alamos Natl Lab, Div Life Sci, Cellular & Mol Biol Grp, Los Alamos, NM 87545 USA. FU NIEHS NIH HHS [ES07845] NR 40 TC 34 Z9 34 U1 0 U2 1 PU AMER ASSOC CANCER RESEARCH PI BIRMINGHAM PA PO BOX 11806, BIRMINGHAM, AL 35202 USA SN 0008-5472 J9 CANCER RES JI Cancer Res. PD MAR 15 PY 1998 VL 58 IS 6 BP 1305 EP 1314 PG 10 WC Oncology SC Oncology GA ZB892 UT WOS:000072518500038 PM 9515820 ER PT J AU Wang, JX Marinkovic, NS Adzic, RR AF Wang, JX Marinkovic, NS Adzic, RR TI Structure of Br adlayers in the course of electrocatalytic reactions O-2 reduction on Pt(111) and Au(100) SO COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS LA English DT Article; Proceedings Paper CT Symposium on Electrochemical Surface Science at the 212th Meeting of the American-Chemical-Society CY AUG 25-29, 1997 CL ORLANDO, FLORIDA SP Amer Chem Soc, Army Res Off DE bromide adlayers; gold electrodes; platinum electrodes; oxygen reduction; X-ray diffraction ID SCANNING-TUNNELING-MICROSCOPY; X-RAY-REFLECTIVITY; OXYGEN REDUCTION; ACID-SOLUTIONS; INTERFACE; ELECTRODE; AU(111); RECONSTRUCTION; DIFFRACTION; BROMIDE AB Structures of Br adlayers were determined on the Pt(111) and Au(100) electrodes in the absence and in the presence of O-2, reduction in 0.1 M HClO4, solutions. On Pt(111), the commensurate (3 x 3) Br adlayer was found between 0.3 and 0.8 V. On Au(100), the c(root 2x2 root 2)R45 degrees and c(root 2 x p)R45 degrees phases were found above 0.35 and 0.68 V, respectively, in agreement with previous work in neutral solutions. O-2 reduction is completely inhibited by the c(root 2 x 2 root 2)R45 degrees phase on Au(100). It takes place only at potentials negative of the low potential limit of the existence of the c(root 2 x 2 root 2)R45 degrees phase. On Pt(111), O-2 reduction is also completely blocked by the (3 x 3) Br adlayer up to 0.5 V. At this potential, the ordered phase vanishes and O, reduction takes place. Adsorbed disordered Br adions change the mechanism of O-2 reduction on Pt(111) from a 4e- into a 2e-reaction. (C) 1998 Elsevier Science B.V. C1 Brookhaven Natl Lab, Dept Appl Sci, Div Chem Sci, Upton, NY 11973 USA. RP Wang, JX (reprint author), Brookhaven Natl Lab, Dept Appl Sci, Div Chem Sci, Upton, NY 11973 USA. RI Wang, Jia/B-6346-2011; Marinkovic, Nebojsa/A-1137-2016 OI Marinkovic, Nebojsa/0000-0003-3579-3453 NR 17 TC 21 Z9 21 U1 0 U2 7 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0927-7757 J9 COLLOID SURFACE A JI Colloid Surf. A-Physicochem. Eng. Asp. PD MAR 15 PY 1998 VL 134 IS 1-2 BP 165 EP 171 DI 10.1016/S0927-7757(97)00326-9 PG 7 WC Chemistry, Physical SC Chemistry GA ZG886 UT WOS:000073049900018 ER PT J AU Von Zimmermann, M Vigliante, A Niemoller, T Ichikawa, N Frello, T Madsen, J Wochner, P Uchida, S Andersen, NH Tranquada, JM Gibbs, D Schneider, JR AF Von Zimmermann, M Vigliante, A Niemoller, T Ichikawa, N Frello, T Madsen, J Wochner, P Uchida, S Andersen, NH Tranquada, JM Gibbs, D Schneider, JR TI Hard-X-ray diffraction study of charge stripe order in La1.48Nd0.4Sr0.12CuO4 SO EUROPHYSICS LETTERS LA English DT Article ID NEUTRON-SCATTERING; FERMI-LIQUID; SPINS; HOLES; SUPERCONDUCTIVITY; FLUCTUATIONS; LA2-XSRXCUO4; NMR AB High-energy photon diffraction is used to investigate the charge ordering previously studied by neutron diffraction in La1.48Nd0.4Sr0.12CuO4. Besides confirming the existence of superlattice peaks due to charge order, the temperature dependence of the peak intensity, width, and position has been determined with improved precision. Furthermore, we show that the scattered intensity has a sinusoidial modulation along c*, consistent with long-range Coulomb interactions between ordered charges within the CuO2 planes. C1 DESY, Hamburger Synchrotronstrahlungslab Hasylab, D-22603 Hamburg, Germany. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. SUNY Stony Brook, Dept Phys, Stony Brook, NY 11794 USA. Univ Tokyo, Supercond Res Course, Bunkyo Ku, Tokyo 113, Japan. Riso Natl Lab, Condensed Matter Phys & Chem Dept, DK-4000 Roskilde, Denmark. RP Von Zimmermann, M (reprint author), DESY, Hamburger Synchrotronstrahlungslab Hasylab, Notkestr 85, D-22603 Hamburg, Germany. RI Tranquada, John/A-9832-2009; Andersen, Niels/A-3872-2012 OI Tranquada, John/0000-0003-4984-8857; NR 20 TC 91 Z9 91 U1 0 U2 5 PU E D P SCIENCES PI LES ULIS CEDEXA PA 7, AVE DU HOGGAR, PARC D ACTIVITES COURTABOEUF, BP 112, F-91944 LES ULIS CEDEXA, FRANCE SN 0295-5075 J9 EUROPHYS LETT JI Europhys. Lett. PD MAR 15 PY 1998 VL 41 IS 6 BP 629 EP 634 PG 6 WC Physics, Multidisciplinary SC Physics GA ZD594 UT WOS:000072702200008 ER PT J AU Bergstrom, DE Grieco, DA Sonti, MM Fawcett, JJ Bell-Prince, C Cram, LS Narayanswami, S Simpson, EM AF Bergstrom, DE Grieco, DA Sonti, MM Fawcett, JJ Bell-Prince, C Cram, LS Narayanswami, S Simpson, EM TI The mouse Y chromosome: Enrichment sizing, and cloning by bivariate flow cytometry SO GENOMICS LA English DT Article ID DNA LIBRARIES; HUMAN GENOME; MOLECULAR CHARACTERIZATION; NUCLEOTIDE-SEQUENCE; X-CHROMOSOME; MUS-MUSCULUS; GENUS MUS; CONSTRUCTION; KARYOTYPE; SPRETUS AB In this report, we demonstrate the utility of interleukin-a (IL-2) stimulation of spleen cell cultures and bivariate flow cytometry in the analysis and purification of the C57BL/6J mouse Y Chromosome. We determined that the DNA content of the C57BL/6J Y Chromosome is approximately 94.7 Mb, making it similar in size to human Chromosome 16 and significantly larger than previous estimates. In addition, we describe the bulk isolation of mouse Y Chromosomes and demonstrate enrichment of the isolated material using a fluorescence in situ hybridization strategy. We detail the construction of two small insert Y Chromosome-specific libraries, ideal for sampling Y Chromosome sequences. From these libraries 1566 clones were analyzed. We provide a detailed characterization of 103 clones, generating nearly 50 kb of sequence. For 30 of these clones, we identify regions of homology to known Y chromosomal sequences, confirming the enrichment of the sorted DNA. From the remaining characterized clones, we describe the development of 15 male-specific PCR assays and 19 male-female PCR assays potentially originating from the pseudoautosomal region or other areas of X-Y or autosome-Y homology. (C) 1998 Academic Press. C1 Jackson Lab, Bar Harbor, ME 04609 USA. Univ Calif Los Alamos Natl Lab, Natl Flow Cytometry Resource, Los Alamos, NM 87545 USA. RP Simpson, EM (reprint author), Jackson Lab, 600 Main St, Bar Harbor, ME 04609 USA. EM ems@jax.org RI Simpson, Elizabeth/H-1183-2012 FU NCI NIH HHS [CA34196]; NCRR NIH HHS [RR01315]; NHGRI NIH HHS [F32 HG000150, F32 HG000150-01] NR 39 TC 9 Z9 9 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0888-7543 J9 GENOMICS JI Genomics PD MAR 15 PY 1998 VL 48 IS 3 BP 304 EP 313 DI 10.1006/geno.1997.5176 PG 10 WC Biotechnology & Applied Microbiology; Genetics & Heredity SC Biotechnology & Applied Microbiology; Genetics & Heredity GA ZF473 UT WOS:000072901000004 PM 9545635 ER PT J AU Grimsditch, M Polian, A Brazhkin, V Balitskii, D AF Grimsditch, M Polian, A Brazhkin, V Balitskii, D TI Elastic constants of alpha-GeO2 SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID HIGH-PRESSURE TRANSFORMATION; GEO2 POLYMORPHS; QUARTZ; SIO2; AMORPHIZATION; CRYSTALLINE AB The elastic constants of alpha-GeO2, the quartzlike polymorph of germanium dioxide, have been determined using Brillouin scattering. The data were obtained using a high quality single crystal of alpha-GeO2. When compared with existing data on alpha-SiO2, our results show that the shear constants are considerably softened in GeO2. This could be an indication that the observed pressure induced phase change is related to a shear instability. (C) 1998 American Institute of Physics. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Paris 06, F-75252 Paris 05, France. Russian Acad Sci, Inst High Pressure Phys, Troitsk 142092, Moscow Region, Russia. Moscow MV Lomonosov State Univ, Moscow 117234, Russia. RP Grimsditch, M (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Polian, Alain/E-1555-2017 OI Polian, Alain/0000-0003-2261-9114 NR 27 TC 33 Z9 33 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 15 PY 1998 VL 83 IS 6 BP 3018 EP 3020 DI 10.1063/1.367117 PG 3 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700021 ER PT J AU Zhang, SB Wei, SH Zunger, A AF Zhang, SB Wei, SH Zunger, A TI A phenomenological model for systematization and prediction of doping limits in II-VI and I-III-VI2 compounds SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID AMPHOTERIC NATIVE DEFECTS; MOLECULAR-BEAM EPITAXY; THIN-FILMS; TRANSPORT-PROPERTIES; ZINC-SELENIDE; BAND OFFSETS; P-TYPE; SEMICONDUCTORS; IMPURITIES; ENERGIES AB Semiconductors differ widely in their ability to be doped. As their band gap increases, it is usually possible to dope them either n or p type, but not both. This asymmetry is documented here, and explained phenomenologically in terms of the "doping pinning rule." (C) 1998 American Institute of Physics. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Zhang, SB (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Zunger, Alex/A-6733-2013; Krausnick, Jennifer/D-6291-2013; Zhang, Shengbai/D-4885-2013 OI Zhang, Shengbai/0000-0003-0833-5860 NR 48 TC 288 Z9 289 U1 3 U2 64 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 15 PY 1998 VL 83 IS 6 BP 3192 EP 3196 DI 10.1063/1.367120 PG 5 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700050 ER PT J AU Jochum, J Mears, C Golwala, S Sadoulet, B Castle, JP Cunningham, MF Drury, OB Frank, M Labov, SE Lipschultz, FP Netel, H Neuhauser, B AF Jochum, J Mears, C Golwala, S Sadoulet, B Castle, JP Cunningham, MF Drury, OB Frank, M Labov, SE Lipschultz, FP Netel, H Neuhauser, B TI Modeling the power flow in normal conductor-insulator-superconductor junctions SO JOURNAL OF APPLIED PHYSICS LA English DT Article ID HOT-ELECTRON MICROCALORIMETERS; TUNNEL JUNCTION; X-RAY AB Normal conductor-insulator-superconductor (NIS) junctions promise to be interesting for x-ray and phonon sensing applications, in particular due to the expected self-cooling of the N electrode by the tunneling current. Such cooling would enable the operation of the active element of the sensor below the cryostat temperature and at a correspondingly higher sensitivity. It would also allow the use of MS junctions as microcoolers. At present, this cooling has not been realized in large area junctions (suitable for a number of detector applications). In this article, we discuss a detailed modeling of the heat flow in such junctions; we show how the heat flow into the normal electrode by quasiparticle back-tunneling and phonon absorption from quasiparticle pair recombination can overcompensate the cooling power. This provides a microscopic explanation of the self-heating effects we observe in our large area NIS junctions. The model suggests a number of possible solutions. (C) 1998 American Institute of Physics. C1 Univ Calif Berkeley, Ctr Particle Astrophys, Berkeley, CA 94720 USA. Univ Calif Lawrence Livermore Natl Lab, Phys & Space Technol Directorate, Livermore, CA 94551 USA. San Francisco State Univ, Dept Phys & Astrophys, Thin Film Lab, San Francisco, CA 94132 USA. RP Jochum, J (reprint author), Univ Calif Berkeley, Ctr Particle Astrophys, 301 Le Conte Hall, Berkeley, CA 94720 USA. RI Frank, Matthias/O-9055-2014 NR 11 TC 31 Z9 31 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-8979 J9 J APPL PHYS JI J. Appl. Phys. PD MAR 15 PY 1998 VL 83 IS 6 BP 3217 EP 3224 DI 10.1063/1.367121 PG 8 WC Physics, Applied SC Physics GA ZC998 UT WOS:000072640700054 ER PT J AU Baer, BJ Brown, JM Zaug, JM Schiferl, D Chronister, EL AF Baer, BJ Brown, JM Zaug, JM Schiferl, D Chronister, EL TI Impulsive stimulated scattering in ice VI and ice VII SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID BRILLOUIN SPECTROSCOPY; ELASTIC-CONSTANTS; HIGH-PRESSURE; DENSE H2O; CELL; DIFFRACTION; VELOCITIES; MOONS; STATE; PHASE AB We demonstrate the use of forced thermal Brillouin scattering to obtain acoustic velocities for oriented high-pressure crystals of ice VI and of ice VII. The elastic constants of ice VI and ice VII determined from these measurements compare favorably with classical Brillouin scattering results. (C) 1998 American Institute of Physics. C1 Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA. Univ Washington, Geophys Program, Seattle, WA 98195 USA. Univ Calif Los Alamos Natl Lab, CST6, Los Alamos, NM USA. RP Chronister, EL (reprint author), Univ Calif Riverside, Dept Chem, Riverside, CA 92521 USA. NR 40 TC 13 Z9 13 U1 0 U2 3 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 15 PY 1998 VL 108 IS 11 BP 4540 EP 4544 DI 10.1063/1.475882 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZB604 UT WOS:000072489200021 ER PT J AU Taylor, ST Zhu, YT Blumenthal, WR Stout, MG Butt, DP Lowe, TC AF Taylor, ST Zhu, YT Blumenthal, WR Stout, MG Butt, DP Lowe, TC TI Characterization of Nicalon fibres with varying diameters - Part I - Strength and fracture studies SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID SILICON-CARBIDE FIBER; CERAMIC-MATRIX COMPOSITES; SIC FIBERS; STRUCTURAL CHARACTERIZATION; TENSILE-STRENGTH; PRECURSORS AB Experimental studies have been conducted to examine the strength and fracture behaviour of monofilament Nicalon SiC fibres with diameters ranging from 8 to 22 mu m. The effects of varying fibre diameter, flaw location and flaw population on the mechanical response of individual fibres were investigated by recourse to extensive fractographic analysis performed on fibres fractured under tensile loading. Results indicate that variations in fibre diameter influence the apparent fibre fracture toughness (K-1c), with higher K-1c values observed for decreasing fibre diameters. Observations also suggest that the location of the critical flaw may play a role in the fracture of Nicalon fibres. Tensile strength values are shown to increase as the normalized distance of the critical flaw from the fibre centre increases, while critical flaw population appears to be strongly dependent on location. The ratio of K-1c to geometry factor (Y) is observed to remain constant with varying flaw location. In addition to surface flaws, three distinct internal flaw populations are seen to cause fracture in Nicalon fibres. Based on these experimental findings, a statistical characterization of the strength of Nicalon fibres with varying diameters is presented in Part II of this paper. (C) 1998 Chapman & Hall. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Taylor, ST (reprint author), Univ Calif Berkeley, Dept Mat Sci & Mineral Engn, Berkeley, CA 94720 USA. EM yahu@lanl.gov RI Zhu, Yuntian/B-3021-2008; Butt, Darryl/B-7480-2008 OI Zhu, Yuntian/0000-0002-5961-7422; Butt, Darryl/0000-0003-4501-8864 NR 40 TC 18 Z9 18 U1 1 U2 8 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR 15 PY 1998 VL 33 IS 6 BP 1465 EP 1473 DI 10.1023/A:1004343608115 PG 9 WC Materials Science, Multidisciplinary SC Materials Science GA ZA655 UT WOS:000072387800009 ER PT J AU Zhu, YT Taylor, ST Stout, MG Butt, DP Blumenthal, WR Lowe, TC AF Zhu, YT Taylor, ST Stout, MG Butt, DP Blumenthal, WR Lowe, TC TI Characterization of Nicalon fibres with varying diameters - Part II - Modified Weibull distribution SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID SILICON-CARBIDE FIBERS; COMPOSITE-MATERIALS; CERAMIC FIBERS; CARBON-FIBERS; STRENGTH; OXIDATION AB Diameters vary significantly in a tow of commercial Nicalon(TM) fibres, which is one of the most attractive ceramic reinforcements for structural composites. It was found that the strength distribution of Nicalon fibres could not be adequately characterized using either single- or bi-modal Weibull distribution. A recently proposed modified Weibull distribution can account for the effect of varying diameter in the characterization of fibre strength. To verify the validity of the modified Weibull distribution, comprehensive mechanical testing and fractographic studies have been conducted on Nicalon SiC fibres with diameters varying from 8 to 22 mu m. The experimental results have been reported in Part I. Part II of this paper further modifies the derivation of the modified Weibull distribution to yield a relationship which is similar in form, but soundly based on experimental findings. Factors considered in the modified Weibull distribution include the dependence of fracture toughness and flaw density on fibre diameter, both of which may vary with fibre diameter, as reported in Part I. Comparison with experimental data shows that the current modified Weibull distribution works very well, while both single-modal and bi-modal Weibull distributions are inadequate for describing Nicalon fibres with varying diameters. (C) 1998 Chapman & Hall. C1 Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Los Alamos, NM 87545 USA. RP Zhu, YT (reprint author), Univ Calif Los Alamos Natl Lab, Div Mat Sci & Technol, Mail Stop G755, Los Alamos, NM 87545 USA. EM yzhu@lanl.gov RI Zhu, Yuntian/B-3021-2008; Butt, Darryl/B-7480-2008 OI Zhu, Yuntian/0000-0002-5961-7422; Butt, Darryl/0000-0003-4501-8864 NR 33 TC 9 Z9 9 U1 2 U2 10 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR 15 PY 1998 VL 33 IS 6 BP 1475 EP 1480 DI 10.1023/A:1004395624953 PG 6 WC Materials Science, Multidisciplinary SC Materials Science GA ZA655 UT WOS:000072387800010 ER PT J AU Bartlett, AH Castro, RG AF Bartlett, AH Castro, RG TI Elevated temperature mechanical properties of MoSi2/Si3N4, MoSi2/SiC composites produced by self-propagating high temperature synthesis SO JOURNAL OF MATERIALS SCIENCE LA English DT Article ID STRENGTH; CREEP; FLOW; PLASTICITY; DUCTILITY; MATRIX; DAMAGE AB MoSi2/Si3N4 and MoSi2/SiC composite powders were produced via a novel self-propagating high temperature synthesis technique (SHS) and consolidated both by hot-pressing and plasma spraying. Mechanical testing subsequently was performed under four-point bending at a variety of elevated temperatures and strain rates. Damage accumulation in the hot-pressed materials, either by particle cracking or particle/matrix separation, resulted in composite mechanical properties that were reduced below the level of the unreinforced material. Plasma sprayed materials showed power-law hardening behaviour caused by Mo5Si3 precipitates and increased strain tolerance because of the fine grain size and reduced yield strength of the matrix. (C) 1998 Chapman & Hall. C1 Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Bartlett, AH (reprint author), Norsam Technol, 61 Rover Blvd, Los Alamos, NM 87544 USA. NR 21 TC 18 Z9 18 U1 1 U2 2 PU KLUWER ACADEMIC PUBL PI DORDRECHT PA SPUIBOULEVARD 50, PO BOX 17, 3300 AA DORDRECHT, NETHERLANDS SN 0022-2461 J9 J MATER SCI JI J. Mater. Sci. PD MAR 15 PY 1998 VL 33 IS 6 BP 1653 EP 1660 DI 10.1023/A:1017536408913 PG 8 WC Materials Science, Multidisciplinary SC Materials Science GA ZA655 UT WOS:000072387800032 ER PT J AU Garaizar, FX Gordon, M Shearer, M AF Garaizar, FX Gordon, M Shearer, M TI An elastoplasticity model for antiplane shearing with a non-associative flow rule: Genuine nonlinearity of plastic waves SO JOURNAL OF MATHEMATICAL ANALYSIS AND APPLICATIONS LA English DT Article C1 N Carolina State Univ, Dept Math, Raleigh, NC 27695 USA. N Carolina State Univ, Ctr Res Sci Computat, Raleigh, NC 27695 USA. RP Garaizar, FX (reprint author), Univ Calif Lawrence Livermore Natl Lab, Ctr Appl Sci Comp, POB 808,L-561, Livermore, CA 94551 USA. NR 7 TC 0 Z9 0 U1 0 U2 0 PU ACADEMIC PRESS INC PI SAN DIEGO PA 525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA SN 0022-247X J9 J MATH ANAL APPL JI J. Math. Anal. Appl. PD MAR 15 PY 1998 VL 219 IS 2 BP 344 EP 363 DI 10.1006/jmaa.1997.5817 PG 20 WC Mathematics, Applied; Mathematics SC Mathematics GA ZB922 UT WOS:000072521800010 ER PT J AU Song, XZ Jia, SL Miura, M Ma, JG Shelnutt, JA AF Song, XZ Jia, SL Miura, M Ma, JG Shelnutt, JA TI Electron transfer photosensitized by a tin lipoporphyrin in solution, micelles, and at water-organic solvent interfaces SO JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY LA English DT Article DE electron transfer; tin lipoporphyrin; triethanolamine; ethylenediaminetetraacetic acid ID RESONANCE RAMAN-SPECTRA; SENSITIZED PHOTOREDOX REACTIONS; N-15 SUBSTITUTED DERIVATIVES; IN-OIL MICROEMULSIONS; PORPHYRIN FORCE-FIELD; PI-PI-INTERACTIONS; CHARGE SEPARATION; REVERSE MICELLES; METHYL VIOLOGEN; REDOX PROCESSES AB Electron transfer photosensitized by a tin lipoporphyrin [Sn(IV) octakis((methoxycarbonyl)-methyl)-meso-tetrakis-(((eicosanyloxy)carbonyl)phenyl)-porphyrin (SnLipoP)] is investigated under various solution conditions using a donor-SnLipoP-methylviologen (MV2+) ternary system, where the donor is triethanolamine (TEA) or ethylenediaminetetraacetic acid (EDTA). The photoreaction of SnLipoP is compared with the photoreactions sensitized by common Sn porphyrins like tin protoporphyrin IX (SnPP) and octaethylporphyrin (SnOEP). A constant photoreaction rate is observed in a water/organic solvent (hexane, benzene) two-phase system in which the porphyrin (SnLipoP, SnOEP) is in the organic solvent and MV2+ is in the aqueous phase. The rate is monitored by the change in thr UV-visible absorption spectra produced by aqueous methylviologen radical MV2+. In contrast with the two-phase system, macroscopically us solutions (aqueous SnPP and micellar solutions of SnLipoP, SnPP and SnOEP) give pseudo-logarithmic rates. These electron-transfer processes are completely consistent with reductive primary electron transfer to the tin porphyrin and optical shielding effects. Differences in the rates for SnLipoP and the other Sn porphyrins are explained by structural differences in the porphyrins. In particular, the structure of the porphyrin influences the phase in which the porphyrin resides, its location relative to interfacial regions, and the way it interacts with itself and other system components. (C) 1998 Elsevier Science S.A. C1 Sandia Natl Labs, Mat Theory & Computat Dept, Albuquerque, NM 87185 USA. Univ New Mexico, Dept Chem, Albuquerque, NM 87131 USA. Brookhaven Natl Lab, Dept Med, Upton, NY 11973 USA. RP Shelnutt, JA (reprint author), Sandia Natl Labs, Mat Theory & Computat Dept, POB 5800, Albuquerque, NM 87185 USA. RI Shelnutt, John/A-9987-2009 OI Shelnutt, John/0000-0001-7368-582X NR 59 TC 16 Z9 16 U1 3 U2 6 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 1010-6030 J9 J PHOTOCH PHOTOBIO A JI J. Photochem. Photobiol. A-Chem. PD MAR 15 PY 1998 VL 113 IS 3 BP 233 EP 241 DI 10.1016/S1010-6030(97)00322-5 PG 9 WC Chemistry, Physical SC Chemistry GA ZE299 UT WOS:000072778400006 ER PT J AU Chalk, SG Milliken, J Miller, JF Venkateswaran, SR AF Chalk, SG Milliken, J Miller, JF Venkateswaran, SR TI The US Department of Energy - investing in clean transport SO JOURNAL OF POWER SOURCES LA English DT Article; Proceedings Paper CT 5th Grove Fuel Cell Symposium on Fuel Cells - Investing in a Clean Future CY SEP 22-25, 1997 CL LONDON, ENGLAND DE clean transport; Partnership for a New Generation of Vehicles (PNGV); US Department of Energy (DOE); polymer electrolyte membrane fuel cells; fuel processing AB The US Department of Energy (DOE), together with six other federal agencies and America's three largest car makers, are jointly investing in the development of polymer electrolyte membrane (PEM) fuel cells as a clean and efficient technology for automotive propulsion under the Partnership for a New Generation of Vehicles (PNGV). (PEM is sometimes referred to as 'proton exchange membrane'. The correctness, or otherwise, of that interpretation will depend on the mechanism of apparent proton transfer in the membrane implied). It is anticipated that the successful development of PEM fuel cells (and other long-term technologies) to meet automotive requirements will extend beyond the PNGV's 2004 timeframe for achieving 80 miles per gallon in production prototypes. Given the extraordinary promise of large energy, environmental and economic benefits to the nation from fuel cells and other long-term technologies, the PNGV partners will continue to invest in these technologies beyond 2004. The DOE's Transportation Fuel Cells Program has recently announced US$50 million of new contract awards for focused R&D to overcome critical technical barriers such as fuel-flexible fuel processing technology. The progress achieved toward automotive goals through these and past investments will also enable nearer-term application of fuel cells (e.g. in buses). This paper describes the status of the PNGV program and the key role and technical accomplishments of the DOE Transportation Fuel Cells Program. The DOE's recent investments in new fuel cell R&D activities will be discussed. (C) 1998 Elsevier Science S.A. C1 US DOE, Off Transportat Technol, Washington, DC 20585 USA. Argonne Natl Lab, Argonne, IL 60439 USA. Energet Inc, Columbia, MD USA. RP Chalk, SG (reprint author), US DOE, Off Transportat Technol, 1000 Independence Ave SW, Washington, DC 20585 USA. NR 6 TC 23 Z9 25 U1 0 U2 3 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0378-7753 J9 J POWER SOURCES JI J. Power Sources PD MAR 15 PY 1998 VL 71 IS 1-2 BP 26 EP 35 DI 10.1016/S0378-7753(97)02767-5 PG 10 WC Chemistry, Physical; Electrochemistry; Energy & Fuels; Materials Science, Multidisciplinary SC Chemistry; Electrochemistry; Energy & Fuels; Materials Science GA ZD567 UT WOS:000072699500007 ER PT J AU Fotin, AV Drobyshev, AL Proudnikov, DY Perov, AN MIrzabekov, AD AF Fotin, AV Drobyshev, AL Proudnikov, DY Perov, AN MIrzabekov, AD TI Parallel thermodynamic analysis of duplexes on oligodeoxyribonucleotide microchips SO NUCLEIC ACIDS RESEARCH LA English DT Article ID DENSITY OLIGONUCLEOTIDE ARRAYS; THERMAL-STABILITY; DNA; HYBRIDIZATION; SEQUENCE AB A microchip method has been developed for massive and parallel thermodynamic analyses of DNA duplexes. Fluorescently labeled oligonucleotides were hybridized with oligonucleotides immobilized in the 100 x 100 x 20 mu m gel pads of the microchips. The equilibrium melting curves for all microchip duplexes were measured in real time in parallel for all microchip duplexes. Thermodynamic data for perfect and mismatched duplexes that were obtained using the microchip method directly correlated with data obtained in solution. Fluorescent labels or longer linkers between the gel and the oligonucleotides appeared to have no significant effect on duplex stability. Extending the immobilized oligonucleotides with a four-base mixture from the 3'-end or one or two universal bases (5-nitroindole) from the 3'- and/or 5'-end increased the stabilities of their duplexes. These. extensions were applied to increase the stabilities of the duplexes formed with short oligonucleotides in microchips, to significantly lessen the differences in melting curves of the AT-and GC-rich duplexes, and to improve discrimination of perfect duplexes from those containing poorly recognized terminal mismatches. This study explored a way to increase the efficiency of sequencing by hybridization on oligonucleotide microchips. C1 Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, Argonne, IL 60439 USA. VA Engelhardt Mol Biol Inst, Joint Human Genome Program, Moscow 117984, Russia. Moscow Inst Phys & Technol, Dolgoprudnyi 141700, Russia. RP MIrzabekov, AD (reprint author), Argonne Natl Lab, Ctr Mechanist Biol & Biotechnol, 9700 S Cass Ave, Argonne, IL 60439 USA. EM amir@everest.bim.anl.gov NR 25 TC 166 Z9 170 U1 0 U2 8 PU OXFORD UNIV PRESS PI OXFORD PA GREAT CLARENDON ST, OXFORD OX2 6DP, ENGLAND SN 0305-1048 J9 NUCLEIC ACIDS RES JI Nucleic Acids Res. PD MAR 15 PY 1998 VL 26 IS 6 BP 1515 EP 1521 DI 10.1093/nar/26.6.1515 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZD451 UT WOS:000072687300023 PM 9490800 ER PT J AU Langot, P Vallet, M Brunel, M Ropars, G Bretenaker, F Le Floch, A Choquette, KD AF Langot, P Vallet, M Brunel, M Ropars, G Bretenaker, F Le Floch, A Choquette, KD TI Direct monitoring of the coupling constant in vectorial lasers SO OPTICS COMMUNICATIONS LA English DT Article DE semiconductor lasers; optical bistability and switching ID VERTICAL-CAVITY LASERS; SEMICONDUCTOR-LASERS; POLARIZATION PROPERTIES; SYSTEMS; GAIN AB The partial separation of two laser eigenstates is used to differentially modulate their net gains, hence permitting to demonstrate a simple method to measure the coupling constant C in bistable vectorial lasers. The same experimental setup works equally well for weak coupling. A good agreement between theoretical and experimental values is obtained in both cases. Moreover, the method is applied to the case of external cavity VCSELs used in optical clocking experiments. (C) 1998 Elsevier Science B.V. C1 Univ Rennes 1, Lab Electron Quant Phys Lasers, CNRS, UMR 6627, F-35042 Rennes, France. Sandia Natl Labs, Ctr Compound Semicond Technol, Albuquerque, NM 87185 USA. RP Vallet, M (reprint author), Univ Rennes 1, Lab Electron Quant Phys Lasers, CNRS, UMR 6627, Campus Beaulieu, F-35042 Rennes, France. EM lpl@univ-rennes1.fr RI Bretenaker, Fabien/C-1814-2012 NR 20 TC 5 Z9 5 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0030-4018 J9 OPT COMMUN JI Opt. Commun. PD MAR 15 PY 1998 VL 148 IS 4-6 BP 270 EP 274 DI 10.1016/S0030-4018(97)00633-0 PG 5 WC Optics SC Optics GA ZR724 UT WOS:000074007400011 ER PT J AU Cleri, F Keblinski, P Colombo, L Phillpot, SR Wolf, D AF Cleri, F Keblinski, P Colombo, L Phillpot, SR Wolf, D TI Correlation between atomic structure and localized gap states in silicon grain boundaries SO PHYSICAL REVIEW B LA English DT Article ID TIGHT-BINDING; POLYCRYSTALLINE SILICON; MOLECULAR-DYNAMICS; SI; HYDROGENATION; DENSITY AB Tight-binding molecular-dynamics simulations of a typical high-energy grain boundary in silicon show that its equilibrium atomic structure is similar to that of bulk amorphous silicon and contains coordination defects. The corresponding electronic structure is also amorphouslike, displaying gap states mainly localized around the coordination defects, where large changes in the bond-hybridization character are observed. It is proposed that such coordination defects in disordered high-energy grain boundaries are responsible for the experimentally observed gap states in polycrystalline Si. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. ENEA, Ctr Ric Casaccia, Div Mat Avanzati, I-00100 Rome, Italy. Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Milan, Dipartimento Sci Mat, I-20126 Milan, Italy. INFM, I-20126 Milan, Italy. RP Cleri, F (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI Phillpot, Simon/J-9117-2012; Colombo, Luciano/D-9013-2013; OI Colombo, Luciano/0000-0001-5335-4652; Phillpot, Simon/0000-0002-7774-6535 NR 23 TC 32 Z9 32 U1 1 U2 8 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 11 BP 6247 EP 6250 DI 10.1103/PhysRevB.57.6247 PG 4 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400013 ER PT J AU Hong, S Chou, MY AF Hong, S Chou, MY TI Effect of hydrogen on the surface-energy anisotropy of diamond and silicon SO PHYSICAL REVIEW B LA English DT Article ID SATURATED SI(100) SURFACE; BY-LAYER GROWTH; SI; RECONSTRUCTION; HOMOEPITAXY; NUCLEATION; DEPENDENCE; AG(111); SI(001); SI(111) AB We have evaluated the surface free energies of hydrogen-covered (100), (111), and (110) surfaces of diamond and silicon as a function of the hydrogen chemical potential using first-principles methods. The change in surface-energy anisotropy and equilibrium crystal shape due to hydrogen adsorption is examined. The three low-index facets are affected differently by the presence of hydrogen and unexpected differences are found between diamond and silicon. Taking into account possible formation of local facets on the hydrogen-covered (100) surfaces, we find that the dihydride phase is not stable on both C(100) and Si(100). nor is the 3x1 phase on C(100). C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. RP Hong, S (reprint author), Oak Ridge Natl Lab, Oak Ridge, TN 37831 USA. RI Chou, Mei-Yin/D-3898-2012 NR 28 TC 44 Z9 44 U1 2 U2 13 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 11 BP 6262 EP 6265 DI 10.1103/PhysRevB.57.6262 PG 4 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400017 ER PT J AU Pitarke, JM Eguiluz, AG AF Pitarke, JM Eguiluz, AG TI Surface energy of a bounded electron gas: Analysis of the accuracy of the local-density approximation via ab initio self-consistent-field calculations SO PHYSICAL REVIEW B LA English DT Article ID EXCHANGE-CORRELATION ENERGY; WAVE-VECTOR ANALYSIS; METALLIC SURFACE; FUNCTIONAL THEORY; SYSTEMS AB We report an ab initio evaluation of the surface energy of a simple metal, performed via a coupling-constant integration over the dynamical density-response function. The rapid rate of change of the electron density at the surface is treated exactly. Long-range correlations are treated self-consistently in the random-phase approximation; short-range correlations are included in time-dependent local-density-functional theory. Our results provide a numerical measure of the error introduced by the usual local-density approximation; this error is found to be small. C1 Euskal Herriko Unibertsitatea, Zientzi Fak, Mat Kondentsatuaren Fis Saila, Bilbao 48080, Basque Country, Spain. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Euskal Herriko Unibertsitatea, Zientzi Fak, Mat Kondentsatuaren Fis Saila, 644 Posta Kutxatila, Bilbao 48080, Basque Country, Spain. RI Pitarke, Jose/C-8602-2009 OI Pitarke, Jose/0000-0002-8253-8028 NR 31 TC 59 Z9 59 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 11 BP 6329 EP 6332 DI 10.1103/PhysRevB.57.6329 PG 4 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400034 ER PT J AU Ozolins, V Wolverton, C Zunger, A AF Ozolins, V Wolverton, C Zunger, A TI Cu-Au, Ag-Au, Cu-Ag, and Ni-Au intermetallics: First-principles study of temperature-composition phase diagrams and structures SO PHYSICAL REVIEW B LA English DT Review ID SHORT-RANGE ORDER; 1ST-PRINCIPLES STATISTICAL-MECHANICS; ELECTRONIC-STRUCTURE CALCULATIONS; ABSORPTION FINE-STRUCTURE; TRANSITION-METAL ALLOYS; MONTE-CARLO SIMULATIONS; PLANE-WAVE METHOD; VIBRATIONAL ENTROPY; DISORDERED ALLOYS; X-RAY AB The classic metallurgical systems-noble-metal alloys-that have formed the benchmark for various alloy theories are revisited. First-principles fully relaxed general-potential linearized augmented plane-wave (LAPW) total energies of a few ordered structures are used as input to a mixed-space cluster expansion calculation to study the phase stability, thermodynamic properties, and bond lengths in Cu-Au, Ag-Au, Cu-Ag, and Ni-Au alloys. (i) Our theoretical calculations correctly reproduce the tendencies of Ag-Au and Cu-Au to form compounds and Ni-Au and Cu-Ag to phase separate at T=0 K. (ii) Of all possible structures, Cu3Au (L1(2)) and CuAu (L1(0)) are found to be the most stable low-temperature phases of Cu1-xAux with transition temperatures of 530 K and 660 K, respectively, compared to the experimental values 663 K and approximate to 670 K. The significant improvement over previous first-principles studies is attributed to the more accurate treatment of atomic relaxations in the present work. (iii) LAPW formation enthalpies demonstrate that L1(2), the commonly assumed stable phase of CuAu,, is not the ground state for Au-rich alloys, but rather that ordered (100) superlattices are stabilized. (iv) We extract the nonconfigurational (e.g., vibrational) entropies of formation and obtain large values for the size-mismatched systems: 0.48 k(B)/atom in Ni0.5Au0.5 (T=1100 K), 0.37 k(B)/atom in Cu0.141Ag0.859 (T=1052 K), and 0.16 k(B)/atom in Cu0.5Au0.5 (T=800 K). (v) Using 8 atom/cell special quasirandom structures we study the bond lengths in disordered Cu-Au and Ni-Au alloys and obtain good qualitative agreement with recent extended x-ray-absorption fine-structure measurements. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Ozolins, V (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. RI Wolverton, Christopher/B-7542-2009; Ozolins, Vidvuds/D-4578-2009 NR 133 TC 178 Z9 187 U1 13 U2 103 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 11 BP 6427 EP 6443 DI 10.1103/PhysRevB.57.6427 PG 17 WC Physics, Condensed Matter SC Physics GA ZD807 UT WOS:000072726400046 ER PT J AU Myers, SM Petersen, GA AF Myers, SM Petersen, GA TI Transport and reactions of gold in silicon containing cavities SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON-MICROSCOPY; INDUCED RECONSTRUCTIONS; SI(111) SURFACE; ION-BEAM; DIFFUSION; AU; IMPLANTATION; SI; DEFECTS; KINETICS AB We quantified the strength of Au binding on cavity walls and in precipitates of the Au-Si molten phase within Si over the temperature range 1023-1123 K. Also determined was the diffusivity-solubility product of interstitial Au. These properties were obtained by using ion implantation and annealing to form multiple layers containing cavities or Au-Si precipitates and then measuring by Rutherford backscattering spectrometry the rate and extent of Au redistribution between layers during isothermal heating. Results were incorporated into a diffusion-reaction formalism describing the evolution of the coupled concentrations of interstitial Au, substitutional Au, Si interstitial atoms, and Si vacancies. Cavities were shown to be effective sinks for the gettering of Au from solution in Si. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Myers, SM (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 48 TC 27 Z9 27 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP 7015 EP 7026 DI 10.1103/PhysRevB.57.7015 PG 12 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300046 ER PT J AU Kralik, B Chang, EK Louie, SG AF Kralik, B Chang, EK Louie, SG TI Structural properties and quasiparticle band structure of zirconia SO PHYSICAL REVIEW B LA English DT Article ID ELECTRONIC-STRUCTURE; 3 PHASES; PSEUDOPOTENTIALS; SEMICONDUCTORS; ENERGIES; ZRO2; STATES; OXIDE; CDSE AB We report ab initio calculations of the structural and quasiparticle properties of ZrO2, otherwise known as zirconia. The plane-wave pseudopotential method is used to compute the structural properties of the cubic, tetragonal, and monoclinic phases of zirconia. Oxygen vacancies in the cubic phase are also studied using a supercell approach. The structural parameters, including all internal degrees of freedom of all phases, are relaxed. Excellent agreement is achieved with experiment and with other ab initio calculations available. We compute the quasiparticle band gaps within Hedin's GW approximation using the method of Hybertsen and Louie, and confirm that the quasiparticle approach can be successfully applied to transition-metal oxides if the core-valence overlap is small. We predict the fundamental gap of pure cubic, tetragonal, and monoclinic zirconia to be 5.55 eV, 6.40 eV, and 5.42 eV, respectively. Within the GW approximation, the oxygen vacancy state in the cubic phase is found to be nondegenerate, fully occupied, and well separated from the valence and conduction bands, positioned 2.1 eV below the conduction band edge. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. NR 34 TC 249 Z9 251 U1 10 U2 41 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP 7027 EP 7036 DI 10.1103/PhysRevB.57.7027 PG 10 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300047 ER PT J AU Wang, XS Li, QM Tringides, MC AF Wang, XS Li, QM Tringides, MC TI Effect of a STM tip on the surface-diffusion measurement: A Monte Carlo study SO PHYSICAL REVIEW B LA English DT Article ID COEFFICIENTS; FLUCTUATIONS AB Monte Carlo simulations are performed to study the effect of an electric field on the surface diffusion of adatoms in a method that measures scanning tunneling microscopy tunneling-current fluctuations. The correlation function of the tunneling-current fluctuations is proportional to the adatom density fluctuation. Diffusion coefficients are inversely proportional to the time constant of the correlation function. Both the shape of the correlation and the measured time constant are calculated as a function of the ratio of the temperature to the characteristic electrostatic energy (i.e., strength of the electric field) and as a function of the initiating time of the measurement. The effect of the field is more pronounced when the measurement is carried out in the early nonequilibrium time regime while the adatom density evolves towards its equilibrium distribution under the spatially dependent electrostatic potential due to the electric field. C1 Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. Iowa State Univ, Dept Phys & Astron, Ames, IA 50011 USA. RP Wang, XS (reprint author), Iowa State Univ, US Dept Energy, Ames Lab, Ames, IA 50011 USA. NR 16 TC 7 Z9 7 U1 0 U2 5 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP 7275 EP 7280 DI 10.1103/PhysRevB.57.7275 PG 6 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300076 ER PT J AU Persson, BNJ Zhang, ZY AF Persson, BNJ Zhang, ZY TI Theory of friction: Coulomb drag between two closely spaced solids SO PHYSICAL REVIEW B LA English DT Article ID ELECTRON-ELECTRON SCATTERING; SURFACES; MICROBALANCE AB We calculate the friction force between two metallic bodies with hat surfaces separated by a vacuum slab of thickness d, and moving with a relative velocity upsilon. The separation d is assumed to be so large that the only interaction between the bodies is via the Coulomb field. The friction force depends linearly on the velocity upsilon (for small upsilon) and decays rapidly with increasing d. In most practical cases, the Coulomb drag makes a negligible contribution to the friction force, but it may make an important contribution in some special cases. C1 Forschungszentrum Julich, Inst Festkorperforsch, D-52425 Julich, Germany. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys, Knoxville, TN 37996 USA. RP Persson, BNJ (reprint author), Forschungszentrum Julich, Inst Festkorperforsch, Postfach 1913, D-52425 Julich, Germany. RI Persson, Bo Nils Johan/I-1548-2013 OI Persson, Bo Nils Johan/0000-0003-1535-738X NR 20 TC 37 Z9 38 U1 1 U2 9 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP 7327 EP 7334 DI 10.1103/PhysRevB.57.7327 PG 8 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300082 ER PT J AU Balasubramanian, T Jensen, E Wu, XL Hulbert, SL AF Balasubramanian, T Jensen, E Wu, XL Hulbert, SL TI Large value of the electron-phonon coupling parameter (lambda=1.15) and the possibility of surface superconductivity at the Be(0001) surface SO PHYSICAL REVIEW B LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION AB The electron-phonon coupling parameter lambda(s) at the Be(0001) surface is measured using angle-resolved photoemission and found to be 1.15+/-0.1, more than four times the bulk Be value lambda(b)=0.24. This large value for lambda(s) may imply the existence of an unusual form of surface superconductivity with a correspondingly large transition temperature. C1 Brandeis Univ, Dept Phys, Waltham, MA 02254 USA. Brookhaven Natl Lab, Natl Synchrotron Light Source Dept, Upton, NY 11973 USA. RP Balasubramanian, T (reprint author), Brandeis Univ, Dept Phys, Waltham, MA 02254 USA. NR 19 TC 39 Z9 41 U1 2 U2 11 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP R6866 EP R6869 DI 10.1103/PhysRevB.57.R6866 PG 4 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300026 ER PT J AU Fluegel, B Mascarenhas, A Geisz, JF Olson, JM AF Fluegel, B Mascarenhas, A Geisz, JF Olson, JM TI Second harmonic generation in ordered Ga1-xInxP SO PHYSICAL REVIEW B LA English DT Article ID GAINP2; SPECTROSCOPY AB Reflection second harmonic generation (SHG) has been used to measure the rotation/reflection properties of spontaneously ordered Ga1-xInxP. Particular conditions are identified in which the SHG signal arises solely from the order-induced symmetry breaking of the (4) over bar operation in zinc blende. By extending the usual experimental techniques to the epilayer edges, the point group of ordered Ga1-xInxP was completely determined from optical methods, and the four components of the nonlinear susceptibility were measured. The case of double-variant samples is also discussed. C1 Natl Renewable Energy Lab, Golden, CO 80401 USA. RP Fluegel, B (reprint author), Natl Renewable Energy Lab, Golden, CO 80401 USA. NR 14 TC 13 Z9 13 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP R6787 EP R6790 DI 10.1103/PhysRevB.57.R6787 PG 4 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300006 ER PT J AU Kurdak, C Rimberg, AJ Ho, TR Clarke, J AF Kurdak, C Rimberg, AJ Ho, TR Clarke, J TI Activated transport and scaling behavior in the current-voltage characteristics and Coulomb-blockade oscillations of two-dimensional arrays of metallic islands SO PHYSICAL REVIEW B LA English DT Article ID SMALL JOSEPHSON-JUNCTIONS; 2-DIMENSIONAL ARRAYS; TUNNEL-JUNCTIONS; DYNAMICS; SOLITONS AB We have investigated the transport properties of two-dimensional arrays of normal islands interconnected by tunnel junctions fabricated close to a conducting ground plane. For bias voltages V below a threshold voltage V-th, the current I is thermally activated with an activation energy proportional to V-th-V. For V>V-th, I scales as (V-V-th)(zeta), where zeta=2.01+/-0.04 and 1.58+/-0.04 for two samples. For constant V, I exhibits Coulomb-blockade oscillations as a function of the voltage of the ground plane. The amplitude of these oscillations scales as (V-V-th)(Chi), where Chi=0.68+/-0.18 and 0.31+/-1-0.10 for the same samples, respectively. These values are consistent with our theoretical prediction Chi=(zeta-1)/2. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Kurdak, C (reprint author), Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Rimberg, Alexander/B-8076-2010 NR 15 TC 28 Z9 28 U1 0 U2 3 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP R6842 EP R6845 DI 10.1103/PhysRevB.57.R6842 PG 4 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300020 ER PT J AU Petersen, L Sprunger, PT Hofmann, P Laegsgaard, E Briner, BG Doering, M Rust, HP Bradshaw, AM Besenbacher, F Plummer, EW AF Petersen, L Sprunger, PT Hofmann, P Laegsgaard, E Briner, BG Doering, M Rust, HP Bradshaw, AM Besenbacher, F Plummer, EW TI Direct imaging of the two-dimensional Fermi contour: Fourier-transform STM SO PHYSICAL REVIEW B LA English DT Article ID 2-DIMENSIONAL ELECTRON-GAS; SURFACES; SCATTERING; WAVES AB Direct images of the two-dimensional Fermi contour at a surface can be generated by a Fourier transform (FT) of scanning tunneling microscopy (STM) images taken at low-bias voltages. The origins of the Fermi contour in the FT are the standing waves of electrons near the Fermi energy caused by defects in the surface. Several examples of FT-STM are presented to illustrate the simplicity of this technique. The advantages and limitations of this Fermi contour imaging technique are discussed. C1 Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. Aarhus Univ, Ctr Atom Scale Mat Phys, DK-8000 Aarhus C, Denmark. Louisiana State Univ, Ctr Adv Microstruct & Devices, Baton Rouge, LA 70803 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. Max Planck Gesell, Fritz Haber Inst, D-14195 Berlin, Germany. RP Petersen, L (reprint author), Aarhus Univ, Inst Phys & Astron, DK-8000 Aarhus C, Denmark. RI Besenbacher, Flemming/A-9623-2010; Hofmann, Philip/B-5938-2008 OI Hofmann, Philip/0000-0002-7367-5821 NR 22 TC 68 Z9 68 U1 1 U2 23 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP R6858 EP R6861 DI 10.1103/PhysRevB.57.R6858 PG 4 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300024 ER PT J AU Zandvliet, HJW Swartzentruber, BS Wulfhekel, W Hattink, BJ Poelsema, B AF Zandvliet, HJW Swartzentruber, BS Wulfhekel, W Hattink, BJ Poelsema, B TI Spontaneous formation of an ordered c(4x2)-(2x1) domain pattern on Ge(001) SO PHYSICAL REVIEW B LA English DT Article ID SI(100) SURFACE; BUCKLED DIMERS; SI(001); STRESS; GE; RECONSTRUCTION; MICROSCOPY; REVERSAL; ENERGY AB Scanning-tunneling-microscopy measurements of Ge(001) reveal the presence of an ordered domain pattern consisting of c(4X2) and (2X1) domains arranged in stripes with a width of several dimer row spacings, oriented along the dimer rows. We suggest that the existence of a soft domain wall between the domains combined with a difference in the stress component along the dimer bond for the (2X1) and c(4X2) domains, respectively, can conspire to produce such an ordered domain phase. A simple model based on strain relaxation explains the observed size of the domain pattern. C1 Univ Twente, Dept Appl Phys, NL-7500 AE Enschede, Netherlands. Univ Twente, Ctr Mat Res, NL-7500 AE Enschede, Netherlands. Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Zandvliet, HJW (reprint author), Univ Twente, Dept Appl Phys, POB 217, NL-7500 AE Enschede, Netherlands. RI Wulfhekel, Wulf/E-2533-2011; Zandvliet, Harold/B-6167-2013 OI Wulfhekel, Wulf/0000-0001-6890-643X; NR 22 TC 71 Z9 71 U1 0 U2 4 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 1098-0121 EI 1550-235X J9 PHYS REV B JI Phys. Rev. B PD MAR 15 PY 1998 VL 57 IS 12 BP R6803 EP R6806 DI 10.1103/PhysRevB.57.R6803 PG 4 WC Physics, Condensed Matter SC Physics GA ZE126 UT WOS:000072760300010 ER PT J AU Boyanovsky, D de Vega, HJ Holman, R Kumar, SP Pisarski, RD AF Boyanovsky, D de Vega, HJ Holman, R Kumar, SP Pisarski, RD TI Nonequilibrium evolution of a "tsunami," a high multiplicity initial quantum state: Dynamical symmetry breaking SO PHYSICAL REVIEW D LA English DT Article ID HEAVY-ION COLLISIONS; QUARK-GLUON PLASMA; DISORIENTED CHIRAL CONDENSATE; NUCLEUS-NUCLEUS COLLISIONS; STRONG ELECTRIC-FIELD; HARD THERMAL LOOPS; HOT GAUGE-THEORIES; HIGH-ENERGY; PARTICLE-PRODUCTION; FINITE-TEMPERATURE AB We propose to study the nonequilibrium features of heavy-ion collisions by following the evolution of an initial state with a large number of quanta with a distribution around a momentum \(k) over right arrow(0)\ corresponding to a thin spherical shell in momentum space, a "tsunami." An O(N)(<(Phi)over right arrow>(2))(2) model field theory in the large N limit is used asa framework to study the nonperturbative aspects of the nonequilibrium dynamics including a resummation of the effects of the medium (the initial particle distribution). In a theory where the symmetry is spontaneously broken in the absence of the medium, when the initial number of particles per correlation volume is chosen to be larger than a critical-value the medium effects can restore the symmetry of the initial state. We show that if one begins with such a symmetry-restored, nonthermal, initial state, nonperturbative effects automatically induce spinodal instabilities leading to a dynamical breaking of the symmetry. As a result there is explosive particle production and a redistribution of the particles towards low momentum due to the nonlinearity of the dynamics. The asymptotic behavior displays the onset of Bose condensation of pions and the equation of state at long times is that of an ultrarelativistic gas although the momentum distribution is nonthermal. C1 Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. Univ Paris 06, LPTHE, F-75252 Paris 05, France. Univ Paris 07, F-75252 Paris 05, France. Carnegie Mellon Univ, Dept Phys, Pittsburgh, PA 15213 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Boyanovsky, D (reprint author), Univ Pittsburgh, Dept Phys & Astron, Pittsburgh, PA 15260 USA. NR 96 TC 23 Z9 23 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0556-2821 J9 PHYS REV D JI Phys. Rev. D PD MAR 15 PY 1998 VL 57 IS 6 BP 3653 EP 3669 DI 10.1103/PhysRevD.57.3653 PG 17 WC Astronomy & Astrophysics; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZC753 UT WOS:000072613900044 ER PT J AU Vagnoli, P Bisson, LF AF Vagnoli, P Bisson, LF TI The SKS1 gene of Saccharomyces cerevisiae is required for long-term adaptation of snf3 null strains to low glucose SO YEAST LA English DT Article DE SKS1; snf3; low glucose; over-expression ID HEXOSE TRANSPORTERS; SHUTTLE VECTORS; FISSION YEAST; HXT GENES; EXPRESSION; PROTEIN; FAMILY; SIGNAL AB The SKS1 gene was originally identified as a multicopy suppressor of the growth defect of snf3 null mutations on low glucose concentrations. Snf3p is required for the rapid induction of HXT2 during growth on low substrate concentrations. Loss of Snf3p leads to a dramatic delay in expression of HXT2. Adaptation to low substrate concentrations does not occur in snf3 sks1 double null mutant strains, suggesting that SKS1 is required for the glucose-dependent expression of HXT2 in the absence of Snf3p activity. Over-expression of SKS1 leads to over-expression of Hxt2p, thus explaining the mechanism of suppression of the snf3 defect. SKS1 defines a novel, Snf3p-independent pathway for the expression of Hxt2p. Under certain growth conditions, over-expression of SKS1 itself leads to a growth defect which is diminished in snf3 hxt2 double mutants. This suggests that over-expression of Hxt2p at physiologically inappropriate times is detrimental to the cells. (C) 1998 John Wiley & Sons, Ltd. C1 Univ Calif Lawrence Livermore Natl Lab, Dept Viticulture & Enol, Livermore, CA 95616 USA. RP Bisson, LF (reprint author), Univ Calif Lawrence Livermore Natl Lab, Dept Viticulture & Enol, Livermore, CA 95616 USA. EM lfbisson@ucdavis.edu NR 24 TC 11 Z9 11 U1 1 U2 2 PU JOHN WILEY & SONS LTD PI W SUSSEX PA BAFFINS LANE CHICHESTER, W SUSSEX PO19 1UD, ENGLAND SN 0749-503X J9 YEAST JI Yeast PD MAR 15 PY 1998 VL 14 IS 4 BP 359 EP 369 DI 10.1002/(SICI)1097-0061(19980315)14:4<359::AID-YEA227>3.3.CO;2-R PG 11 WC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Microbiology; Mycology SC Biochemistry & Molecular Biology; Biotechnology & Applied Microbiology; Microbiology; Mycology GA ZE656 UT WOS:000072816400006 PM 9559544 ER PT J AU de Swiet, TM Tomaselli, M Pines, A AF de Swiet, TM Tomaselli, M Pines, A TI NMR spectra with peaks at the principal values of the chemical shielding tensor SO CHEMICAL PHYSICS LETTERS LA English DT Article ID ANGLE-SPINNING NMR; NUCLEAR-MAGNETIC-RESONANCE; MAGIC-ANGLE; SHIFT-ANISOTROPY; ROTARY RESONANCE; POWDERED SOLIDS; SPECTROSCOPY AB The NMR chemical shielding in a solid powder sample produces featured, but broad, lineshapes, or powder patterns, because the shielding experienced by a nuclear spin depends on the spatial orientation of its local molecular frame with respect to the external magnetic field. The Lineshape, however, is fully determined by the three principal values of the shielding tenser. We present a simple approach that uses sample spinning NMR to extract peaks at the principal-value frequencies from chemical shielding powder patterns. Such techniques may simplify spectra with overlapping powder patterns without the information loss inherent in fast magic angle spinning. Experimental data and numerical simulations are presented for two P-31 model compounds. (C) 1998 Elsevier Science B.V. C1 EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP de Swiet, TM (reprint author), EO Lawrence Berkeley Natl Lab, Div Sci Mat, Berkeley, CA 94720 USA. NR 25 TC 10 Z9 10 U1 1 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAR 13 PY 1998 VL 285 IS 1-2 BP 59 EP 63 DI 10.1016/S0009-2614(97)01478-4 PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZF354 UT WOS:000072889100010 ER PT J AU Mebel, AM Lin, SH Pinnaduwage, LA AF Mebel, AM Lin, SH Pinnaduwage, LA TI Potential energy surfaces of excited states of H-2(-) SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CONFIGURATION-INTERACTION METHOD; DISSOCIATIVE ATTACHMENT; 2-SIGMA-U+ RESONANCE; MOLECULAR-HYDROGEN; NEGATIVE-ION; H FORMATION; SCF; COLLISIONS AB Thirteen electronic states of H-2(-) in various symmetries have been calculated using the MRCI/aug-cc-pV5Z approximation. The lowest 2 Sigma(u)(+) and (2) Sigma(g)(+) states have been shown to cross with the X-1 Sigma(g)(+) state of H-2 at the nuclear separation of 1.58 and 2.70 Angstrom and the energies of 3.16 and 4.66 eV, respectively. The surfaces of higher excited states exhibit complex shapes defined by avoided crossings between the states of the same symmetry. Some of the excited H-2(-) and H-2 surfaces cross, and this crossing can be relevant to the electron attachment processes in laser-irradiated H-2. (C) 1998 Elsevier Science B.V. C1 Acad Sinica, Inst Atom & Mol Sci, Taipei 10764, Taiwan. Oak Ridge Natl Lab, Div Life Sci, Oak Ridge, TN 37831 USA. RP Mebel, AM (reprint author), Acad Sinica, Inst Atom & Mol Sci, POB 23-166, Taipei 10764, Taiwan. RI Mebel, Alexander/A-5234-2009 NR 34 TC 3 Z9 3 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAR 13 PY 1998 VL 285 IS 1-2 BP 114 EP 120 DI 10.1016/S0009-2614(98)00021-9 PG 7 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZF354 UT WOS:000072889100018 ER PT J AU Ryu, KS Lee, HY Kim, SP Beauchamp, J Tung, CS Isaacs, NW Ji, IH Ji, TH AF Ryu, KS Lee, HY Kim, SP Beauchamp, J Tung, CS Isaacs, NW Ji, IH Ji, TH TI Modulation of high affinity hormone binding - Human choriogonadotropin binding to the exodomain of the receptor is influenced by exoloop 2 of the receptor SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID EXTRACELLULAR DOMAIN; LUTROPIN/CHORIOGONADOTROPIN RECEPTOR; TRANSMEMBRANE DOMAIN; ACTIVATION; RESIDUES; LYS(583); LOOP AB The lutropin/choriogonadotropin receptor is a seven-transmembrane receptor and consists of two major domains of similar size, an extracellular exodomain and a membrane-associated endodomain which includes 3 exoloops. The uniquely large exodomain is responsible for high affinity hormone binding whereas receptor activation occurs at the endodomain. However, little is known about the relationship between the exodomain and endodomain. It was reported that hormone binding to the exodomain was improved when the endodomain was truncated. This result suggests that hormone binding to the exodomain was influenced by the endodomain. To test this hypothesis, amino acids of exoloop 2 were examined by Ala substitutions. The binding affinity was enhanced by some Ala substitutions but attenuated by others. These results indicate that exoloop 2 influences the hormone binding to the exodomain. Particularly, the high affinity hormone binding at the exodomain is constrained by a group of amino acids, Ser(484), ASn(485), Lys(488), Ser(490), and Ser(499). Computer modeling suggests these residues may be positioned on one side of exoloop 2. It also influences the affinity for cAMP induction and the maximal cAMP production in distinct ways, in addition to its influence on the hormone binding affinity. The distinct ways of influencing these functions are sometimes in conflict and compromised to attain the maximal affinity for cAMP induction. As a result, the exodomain attains the maximal affinity for hormone binding when the endodomain is truncated and cAMP induction is disengaged. C1 Univ Wyoming, Dept Mol Biol, Laramie, WY 82071 USA. Univ Glasgow, Dept Chem, Glasgow G12 8QQ, Lanark, Scotland. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. RP Ji, TH (reprint author), Univ Wyoming, Dept Mol Biol, Laramie, WY 82071 USA. EM Ji@uwyo.edu FU NICHD NIH HHS [HD-18702]; NIDDK NIH HHS [DK-51469] NR 22 TC 35 Z9 35 U1 0 U2 0 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD MAR 13 PY 1998 VL 273 IS 11 BP 6285 EP 6291 DI 10.1074/jbc.273.11.6285 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZB597 UT WOS:000072488500047 PM 9497355 ER PT J AU Lee, X Thompson, A Zhang, ZM Ton-that, H Biesterfeldt, J Ogata, C Xu, LL Johnston, RAZ Young, NM AF Lee, X Thompson, A Zhang, ZM Ton-that, H Biesterfeldt, J Ogata, C Xu, LL Johnston, RAZ Young, NM TI Structure of the complex of Maclura pomifera agglutinin and the T-antigen disaccharide, Gal beta 1,3GalNAc SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID THOMSEN-FRIEDENREICH-ANTIGEN; ADULT-RAT LUNG; RICIN-B-CHAIN; ARTOCARPUS-INTEGRIFOLIA; BINDING GLYCOPROTEIN; LECTIN; JACALIN; SPECIFICITY; SITE; FORMS AB Maclura pomifera agglutinin is a tetrameric plant seed lectin with high affinity for the tumor-associated T-antigen disaccharide, Gal beta 1,3GalNAc alpha, and hence for many O-linked glycopeptide structures, Unlike members of most lectin families, it lacks both metal ions and Cys residues. The structure of its complex with Gal beta 1,3GalNAc was determined to 2.2 Angstrom by first using multiwavelength anomalous diffraction with a lead derivative of the native protein, and then using molecular replacement with the unrefined structure as a model to solve the structure of the complex. The subunits share the beta-prism architecture and three-fold pseudo-symmetry of the related lectin jacalin, with the 21-residue beta-chains in the center of the tetramer, Interactions with the GalNAc predominate in the binding of the disaccharide. It forms a network of H-bonds with only one side chain, from an Asp residue, the amino group of the N-terminal Gly of the alpha-chain, and peptide backbone atoms of two aromatic residues. The Gal moiety does not H-bond directly with residues in the same monomer, i.e. there is no true subsite for it, but there are interactions through two water molecules. In the crystal, it interacts with residues in the binding site of an adjacent tet tetramer. The minimum energy conformation expected for the disaccharide is retained, despite its mediating the tetramer tetramer interactions in the crystal packing. The resulting lattice is comparable to those seen for complexes of other lectins with branched glycopeptides. C1 Cleveland Clin Fdn, Res Inst, Dept Canc Biol, Cleveland, OH 44195 USA. European Synchrotron Radiat Facil, F-38042 Grenoble, France. Brookhaven Natl Lab, Howard Hughes Med Inst, Natl Synchrotron Light Source, Upton, NY 11973 USA. Natl Res Council Canada, Inst Biol Sci, Ottawa, ON K1A 0R6, Canada. RP Lee, X (reprint author), Cleveland Clin Fdn, Res Inst, Dept Canc Biol, Cleveland, OH 44195 USA. NR 37 TC 78 Z9 82 U1 0 U2 2 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD MAR 13 PY 1998 VL 273 IS 11 BP 6312 EP 6318 DI 10.1074/jbc.273.11.6312 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZB597 UT WOS:000072488500051 PM 9497359 ER PT J AU Wang, JS Yoo, Y Gao, C Takeuchi, I Sun, XD Chang, HY Xiang, XD Schultz, PG AF Wang, JS Yoo, Y Gao, C Takeuchi, I Sun, XD Chang, HY Xiang, XD Schultz, PG TI Identification of a blue photoluminescent composite material from a combinatorial library SO SCIENCE LA English DT Article ID SILICON AB A quaternary combinatorial masking strategy was used in conjunction with photolithography to generate compositionally diverse thin-film phosphor libraries containing 1024 different compositions on substrates 2.5 centimeters square, A parallel imaging system and scanning spectrophotometer were used to identify and characterize compositions in the library with interesting luminescent behavior. Optimal compositions were identified with the use of gradient libraries, in which the stoichiometry of a material was varied continuously, This process led to the identification of an efficient blue photoluminescent composite material, Gd3Ga5O12/SiO2. Experimental evidence suggests that luminescence in this material may arise from interfacial effects between SiO2 and Gd3Ga5O12. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Howard Hughes Med Inst, Berkeley, CA 94720 USA. RP Xiang, XD (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RI Xiang, Xiaodong/A-9445-2012; Xiang, Xiaodong/A-5936-2017 NR 17 TC 238 Z9 265 U1 6 U2 52 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 13 PY 1998 VL 279 IS 5357 BP 1712 EP 1714 DI 10.1126/science.279.5357.1712 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZB612 UT WOS:000072490000053 ER PT J AU Yost, FG AF Yost, FG TI The triple line in reactive wetting SO SCRIPTA MATERIALIA LA English DT Article C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Yost, FG (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. NR 6 TC 9 Z9 10 U1 0 U2 2 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD MAR 13 PY 1998 VL 38 IS 8 BP 1225 EP 1228 DI 10.1016/S1359-6462(98)00030-X PG 4 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA ZF038 UT WOS:000072856500007 ER PT J AU Ruano, OA Sherby, OD Wadsworth, J Wolfenstine, J AF Ruano, OA Sherby, OD Wadsworth, J Wolfenstine, J TI Diffusional creep and diffusion-controlled dislocation creep and their relation to denuded zones in Mg-ZrH2 materials SO SCRIPTA MATERIALIA LA English DT Article ID HARPER-DORN CREEP; TEMPERATURES; DEFORMATION; REFUTATION; DEFENSE; METALS C1 CSIC, Ctr Nacl Invest Met, Dept Met Phys, E-28040 Madrid, Spain. Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Univ Texas, Div Engn, San Antonio, TX 78249 USA. RP Ruano, OA (reprint author), CSIC, Ctr Nacl Invest Met, Dept Met Phys, Av Gregorio del Amo 8, E-28040 Madrid, Spain. RI Ruano, Oscar/H-1835-2015 OI Ruano, Oscar/0000-0001-6368-986X NR 30 TC 19 Z9 20 U1 0 U2 3 PU PERGAMON-ELSEVIER SCIENCE LTD PI OXFORD PA THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND SN 1359-6462 J9 SCRIPTA MATER JI Scr. Mater. PD MAR 13 PY 1998 VL 38 IS 8 BP 1307 EP 1314 DI 10.1016/S1359-6462(98)00021-9 PG 8 WC Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Science & Technology - Other Topics; Materials Science; Metallurgy & Metallurgical Engineering GA ZF038 UT WOS:000072856500019 ER PT J AU Letellier, SR Lochhead, MJ Campbell, AA Vogel, V AF Letellier, SR Lochhead, MJ Campbell, AA Vogel, V TI Oriented growth of calcium oxalate monohydrate crystals beneath phospholipid monolayers SO BIOCHIMICA ET BIOPHYSICA ACTA-GENERAL SUBJECTS LA English DT Article DE calcium oxalate; monolayer; mineralization; phospholipid; dipalmitoylphosphatidylcholine; dimyristoylphosphatidylserine ID COMPRESSED LANGMUIR MONOLAYERS; WATER-INTERFACE; NUCLEATION; FILMS; DIHYDRATE; PHASE; PHOSPHATIDYLSERINE; WHEWELLITE; ACIDS; MODEL AB Oriented calcium oxalate crystals have been grown beneath phospholipid monolayers at the air-solution interface from supersaturated calcium oxalate solutions. Mature calcium oxalate crystals grown beneath zwitterionic dipalmitoylphosphatidylcholine (DPPC) monolayers exhibit the characteristic morphology of calcium oxalate monohydrate (COM) crystals with the elongated ((1) over bar 01) crystal face preferentially oriented parallel to the plane of the monolayer. Calcium oxalate crystals grown beneath negatively-charged dimyristoylphosphatidylserine (DMPS) monolayers also show a preferential orientation with respect to the monolayer; they do not, however, exhibit the characteristic COM morphology. Raman spectroscopy strongly suggests that the crystals grown beneath either DPPC or DMPS monolayers are the monohydrate phase of calcium oxalate; therefore, differences in crystal morphology are not due to differences in the crystalline phase. Dimyristoylphosphatidylethanolamine (DMPE), dimyristoylphosphatidic acid (DMPA), eicosanoic acid (C(20)), and eicosanol (C(20)-OH) monolayers have also been studied to help elucidate the mechanisms of interaction between the lipid monolayers and the calcium oxalate crystals. We discuss the roles of lattice matching, hydrogen bonding, stereochemistry and electrostatics on crystal orientation and morphology. (C) 1998 Elsevier Science B.V. C1 Univ Washington, Dept Bioengn, Seattle, WA 98195 USA. Pacific NW Natl Lab, Dept Chem & Mat Sci, Richland, WA USA. RP Vogel, V (reprint author), Univ Washington, Dept Bioengn, Seattle, WA 98195 USA. EM vogel@bioeng.washington.edu RI Vogel, Viola/O-8025-2015 OI Vogel, Viola/0000-0003-2898-7671 NR 45 TC 47 Z9 53 U1 0 U2 15 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0304-4165 J9 BBA-GEN SUBJECTS JI Biochim. Biophys. Acta-Gen. Subj. PD MAR 12 PY 1998 VL 1380 IS 1 BP 31 EP 45 DI 10.1016/S0304-4165(97)00121-9 PG 15 WC Biochemistry & Molecular Biology; Biophysics SC Biochemistry & Molecular Biology; Biophysics GA ZD556 UT WOS:000072698400004 PM 9545525 ER PT J AU Maya, L Hagaman, EW Williams, RK Wang, XD Del Cul, GD Fiedor, JN AF Maya, L Hagaman, EW Williams, RK Wang, XD Del Cul, GD Fiedor, JN TI Carbon in alpha-platinum dioxide SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID OXIDE-FILMS; COPPER; XPS AB Carbon in the form of hydrocarbons was found chemisorbed on alpha-PtO2. The sorption process, observed in the laboratory, occurs readily in the absence of a deliberate source, and it is faster on thin sputtered films as compared with powder samples. Carbon present in alpha-PtO2 is tenaciously held, and it has the effect of lowering the decomposition temperature of the pure oxide. The decomposition proceeds without the formation of intermediate oxidation species of platinum to yield carbon dioxide and the metal. An intercalated carbon species in platinum oxide, initially suspected, was not formed in the course of this study, but it would be an interesting material if a synthetic pathway could be found for such an oxide, predicted by theory to be a metallic conductor. C1 Oak Ridge Natl Lab, Div Chem & Analyt Sci, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA. Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. Mat & Chem Lab, Oak Ridge, TN 37831 USA. RP Maya, L (reprint author), Oak Ridge Natl Lab, Div Chem & Analyt Sci, POB 2008, Oak Ridge, TN 37831 USA. NR 22 TC 16 Z9 16 U1 0 U2 1 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 12 PY 1998 VL 102 IS 11 BP 1951 EP 1955 DI 10.1021/jp9802331 PG 5 WC Chemistry, Physical SC Chemistry GA ZC825 UT WOS:000072621900017 ER PT J AU Lee, JW Collins, RT Greenbaum, E AF Lee, JW Collins, RT Greenbaum, E TI Molecular ionic probes: A new class of hill reagents and their potential for nanofabrication and biometallocatalysis SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID PLATINIZED CHLOROPLASTS; PHOTOSYSTEM-I; PHOTOCATALYTIC MATERIAL; PHOTOCURRENTS; ELECTRONICS; PH AB We report the results of an extensive experimental survey and characterization of over 20 species of transition-metal compounds for their activity in the Hill reaction and photoprecipitation of metal at the lipid-water interface of photosynthetic thylakoid membranes. Four new Hill reagents were identified: PtCl4, OsCl3, [RuCl6](2-), and [RuCl6](3-). Each can be photosynthetically reduced to form a metallic catalyst at the reducing site of photosystem I (PSI) in the thylakoid membranes. Negative charge of the metal-compound species is apparently essential for their interaction with the reducing site of PSI. When PtCl4 and OsCl3 an dissolved in water, they combine with water molecules to form H-2[PtCl4(OH)(2)] and H-3[OsCl3(OH)(3)], which can dissociate to negatively charged species [PtCl4(OH)(2)](2-) and [OsCl3(OH)(3)](3-) at neutral pH. Metallic ruthenium can also catalyze reduction of protons for H-2 production, in addition to its known catalytic ability to fix CO2. These findings could have important implications for nanofabrication and biometallocatalysis to harness the power of photosynthetic systems. C1 Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. RP Lee, JW (reprint author), Oak Ridge Natl Lab, Div Chem Technol, Oak Ridge, TN 37831 USA. NR 24 TC 14 Z9 14 U1 2 U2 5 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5647 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 12 PY 1998 VL 102 IS 11 BP 2095 EP 2100 DI 10.1021/jp973058h PG 6 WC Chemistry, Physical SC Chemistry GA ZC825 UT WOS:000072621900037 ER PT J AU Dohrmann, CR AF Dohrmann, CR TI Dynamics of a tire-wheel-suspension assembly SO JOURNAL OF SOUND AND VIBRATION LA English DT Article ID NATURAL FREQUENCIES; ROLLING-CONTACT; ROTATING RINGS AB A method is presented for the dynamic analysis of a tire-wheel-suspension assembly. The suspension, modelled by linear spring and dashpot elements, is connected to the center of a rigid wheel rotating at a constant angular rate. The tire is modelled as an inextensible circular ring on a foundation connected to the wheel. A distinguishing feature of the method is that tire deformations are expressed as functions of a fixed-frame rather than a rotating-frame co-ordinate. With such an approach, the equations of motion are expressed as a linear, time-invariant system. This is in stark contrast to previously published results in which a parametrically excited system with periodic coefficients is obtained. Advantages of the method include: (1) stability can be determined from an eigenvalue analysis rather than from Floquet analysis which requires numerical time integration, and (2) modal characteristics of the system in rolling contact can be readily determined. Results are presented which show the effects of rotation and damping on the static response of a tire in rolling contact with a flat, frictionless surface. The effects of rotation on the frequencies and damping ratios of the system are also presented. (C) 1998 Academic Press Limited. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Dohrmann, CR (reprint author), Sandia Natl Labs, Mail Stop 0439, Albuquerque, NM 87185 USA. NR 21 TC 16 Z9 20 U1 0 U2 3 PU ACADEMIC PRESS LTD PI LONDON PA 24-28 OVAL RD, LONDON NW1 7DX, ENGLAND SN 0022-460X J9 J SOUND VIB JI J. Sound Vibr. PD MAR 12 PY 1998 VL 210 IS 5 BP 627 EP 642 DI 10.1006/jsvi.1997.1332 PG 16 WC Acoustics; Engineering, Mechanical; Mechanics SC Acoustics; Engineering; Mechanics GA ZF967 UT WOS:000072951200005 ER PT J AU Norman, MR Ding, H Randeria, M Campuzano, JC Yokoya, T Takeuchi, T Takahashi, T Mochiku, T Kadowaki, K Guptasarma, P Hinks, DG AF Norman, MR Ding, H Randeria, M Campuzano, JC Yokoya, T Takeuchi, T Takahashi, T Mochiku, T Kadowaki, K Guptasarma, P Hinks, DG TI Destruction of the Fermi surface underdoped high-T-c superconductors SO NATURE LA English DT Article ID ANGLE-RESOLVED PHOTOEMISSION; NORMAL-STATE; ELECTRONIC-STRUCTURE; BI2SR2CACU2O8+DELTA; GAP AB The Fermi surface-the set of points in momentum space describing gapless electronic excitations-is a central concept in the theory of metals. In this context, the normal 'metallic' state of the optimally doped high-temperature superconductors is not very unusual: above the superconducting transition temperature, T-c, there is evidence for a large Fermi surface(1-3) despite the absence of well-defined elementary excitations. In contrast, the normal state of underdoped high-temperature superconductors differs in that there is evidence for a 'pseudogap' above T-c (refs 4-6). Here we examine, using angle-resolved photoemission spectroscopy, the temperature dependence of the Fermi surface in underdoped Bi2Sr2CaCu2O8+delta. We find that, on cooling the sample, the pseudogap opens up at different temperatures for different points in momentum space. This leads to an initial breakup of the Fermi surface, at a temperature T*, into disconnected arcs, which then shrink with decreasing temperature before collapsing to the point nodes of the superconducting ground state below T-c. This unusual behaviour, where the Fermi surface does not form a continuous contour in momentum space as in conventional metals, is unprecedented in that it occurs in the absence of long-range order. Moreover, although the superconducting gap below T-c evolves smoothly into the pseudogap above T-c, the pseudogap differs in its unusual temperature-dependent anisotropy, implying an intimate but non-trivial relationship between the pseudogap and the superconducting gap. C1 Argonne Natl Lab, Div Mat Sci, Argonne, IL 60439 USA. Univ Illinois, Dept Phys, Chicago, IL 60607 USA. Tata Inst Fundamental Res, Mumbai 400005, India. Tohoku Univ, Dept Phys, Sendai, Miyagi 980, Japan. Nagoya Univ, Dept Crystalline Mat Sci, Nagoya, Aichi 46401, Japan. Natl Res Inst Met, Ibaraki, Osaka 305, Japan. Univ Tsukuba, Inst Mat Sci, Ibaraki, Osaka 305, Japan. RP Campuzano, JC (reprint author), Argonne Natl Lab, Div Mat Sci, 9700 S Cass Ave, Argonne, IL 60439 USA. RI YOKOYA, Takayoshi/B-1478-2011; Takahashi, Takashi/E-5080-2010; Tohoku, Arpes/A-4890-2010; Norman, Michael/C-3644-2013 OI Ding, Hong/0000-0003-4422-9248; NR 12 TC 789 Z9 797 U1 4 U2 64 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAR 12 PY 1998 VL 392 IS 6672 BP 157 EP 160 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZB349 UT WOS:000072462700054 ER PT J AU Genick, UK Soltis, SM Kuhn, P Canestrelli, IL Getzoff, ED AF Genick, UK Soltis, SM Kuhn, P Canestrelli, IL Getzoff, ED TI Structure at 0.85 angstrom resolution of an early protein photocycle intermediate SO NATURE LA English DT Article ID PHOTOACTIVE YELLOW PROTEIN; LINKED 4-HYDROXYCINNAMYL CHROMOPHORE; ECTOTHIORHODOSPIRA-HALOPHILA; PHOTOTROPHIC BACTERIUM; CRYSTALLOGRAPHY; SPECTROSCOPY; TEMPERATURE; CRYSTALS AB Protein photosensors from all kingdoms of life(1,2) use bound organic molecules, known as chromophores, to detect light, A specific double bond within each chromophore is isomerized by light, triggering slower changes in the protein as a whole, The initial movements of the chromophore, which can occur in femtoseconds, are tightly constrained by the surrounding protein, making it difficult to see how isomerization can occur, be recognized, and be appropriately converted into a protein-wide structural change and biological signal, Here we report how this dilemma is resolved in the photoactive yellow protein (PYP). We trapped a key early intermediate in the light cycle of PYP at temperatures below -100 degrees C, and determined its structure at better than 1 Angstrom resolution, The 4-hydroxycinnamoyl chromophore(3,4) isomerizes by flipping its thioester linkage with the protein, thus avoiding collisions resulting from large-scale movement of its aromatic ring during the initial light reaction, A protein-to-chromophore hydrogen bond that is present in both the preceding dark state(5) and the subsequent signalling state(6) of the photosensor breaks, forcing one of the hydrogen-bonding partners into a hydrophobic pocket. The isomerized bond is distorted into a conformation resembling that in the transition state. The resultant stored energy is used to drive the PYP light cycle. These results suggest a model for phototransduction, with implications for bacteriorhodopsin(7,8), photoactive proteins(1,2), PAS domains(9), and signalling proteins. C1 Scripps Res Inst, Dept Mol Biol, La Jolla, CA 92037 USA. Scripps Res Inst, Skaggs Inst Chem Biol, La Jolla, CA 92037 USA. Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. RP Getzoff, ED (reprint author), Scripps Res Inst, Dept Mol Biol, 10550 N Torrey Pines Rd, La Jolla, CA 92037 USA. NR 27 TC 295 Z9 301 U1 1 U2 14 PU MACMILLAN MAGAZINES LTD PI LONDON PA PORTERS SOUTH, 4 CRINAN ST, LONDON, ENGLAND N1 9XW SN 0028-0836 J9 NATURE JI Nature PD MAR 12 PY 1998 VL 392 IS 6672 BP 206 EP 209 PG 4 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZB349 UT WOS:000072462700069 PM 9515969 ER PT J AU Adams, AA Mitchell, GE Shriner, JF AF Adams, AA Mitchell, GE Shriner, JF TI Statistical distribution of reduced transition probabilities in Al-26 SO PHYSICS LETTERS B LA English DT Article ID SPECTRAL FLUCTUATION PROPERTIES; MODEL EIGENVECTOR COMPONENTS; SHELL-MODEL; STRENGTH FLUCTUATIONS; ACOUSTIC RESONANCES; QUANTUM CHAOS; ENERGY-LEVELS; NUCLEI; MG-25(P,GAMMA)AL-26; SYSTEMS AB Reduced electromagnetic transition matrix elements were determined for levels in Al-26 from the ground state to 8 MeV. In this energy region in Al-26, states with isospin 0 and 1 coexist, and isospin is approximately 97% conserved. These data provide the first test of the effect of symmetry breaking on the transition matrix element distribution. The experimental distribution deviates significantly from the Porter-Thomas distribution. (C) 1998 Elsevier Science B.V. C1 N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. Triangle Univ Nucl Lab, Durham, NC 27708 USA. Tennessee Technol Univ, Dept Phys, Cookeville, TN 38505 USA. RP Adams, AA (reprint author), Univ Calif Los Alamos Natl Lab, POB 1663, Los Alamos, NM 87545 USA. NR 39 TC 30 Z9 30 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 12 PY 1998 VL 422 IS 1-4 BP 13 EP 18 DI 10.1016/S0370-2693(98)00031-8 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK629 UT WOS:000073344400003 ER PT J AU Srivastava, DK Geiger, K AF Srivastava, DK Geiger, K TI Spectra of produced particles at CERN SPS heavy-ion collisions from a parton cascade model SO PHYSICS LETTERS B LA English DT Article ID NUCLEUS-NUCLEUS COLLISIONS; ULTRARELATIVISTIC ENERGIES; HADRONIC-INTERACTIONS; DYNAMICS; VENUS; FLOW AB We evaluate the spectra of produced particles (pions, kaons, antiprotons) from partonic cascades which may develop in the wake of heavy-ion collisions at CERN SPS energies and which may hadronize by formation of clusters which decay into hadrons. Using the experimental data obtained by NA35 and NA44 collaborations for S + S and Pb + Pb collisions, we conclude that the Monte Carlo implementation of the recently developed parton-cascade/cluster-hadronization model provides a reasonable description of the distributions of the particles produced in such collisions. While the rapidity distribution of the mid-rapidity protons is described reasonably well, their transverse momentum distribution falls too rapidly compared to the experimental values, implying a significant effect of final state scattering among the produced hadrons neglected so far. (C) 1998 Elsevier Science B.V. C1 Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, Calcutta 700064, W Bengal, India. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Srivastava, DK (reprint author), Bhabha Atom Res Ctr, Ctr Variable Energy Cyclotron, 1-AF Bidhan Nagar, Calcutta 700064, W Bengal, India. NR 32 TC 11 Z9 11 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 12 PY 1998 VL 422 IS 1-4 BP 39 EP 44 DI 10.1016/S0370-2693(98)00048-3 PG 6 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK629 UT WOS:000073344400007 ER PT J AU Galindo-Uribarri, A Ward, D Ball, GC Janzen, VP Radford, DC Ragnarsson, I Headly, D AF Galindo-Uribarri, A Ward, D Ball, GC Janzen, VP Radford, DC Ragnarsson, I Headly, D TI A smoothly terminating rotational band in Zn-64 SO PHYSICS LETTERS B LA English DT Article AB A rotational band has been discovered in the nucleus Zn-64; it extends from spin (12 (h) over bar) to spin (24 (h) over bar), and exhibits strong dipole transitions between its signature partners. In our interpretation, Zn-64 takes on triaxial deformation (epsilon similar to-0.3 gamma similar to 30 degrees) at intermediate spin when an f(7/2) proton is promoted across the spherical shell-gap at Z = 28 to the g(9/2) orbital. The situation is parallel to that occurring in the smooth terminating bands in the Sn and Sb isotopes at the Z = 50 shell-gap. The band in Zn-64 is the first example of a collective band approaching termination in the mass A similar to 60 region. Crown Copyright (C) 1998 Published by Elsevier Science B.V. C1 AECL Res, Chalk River Labs, Chalk River, ON K0J 1J0, Canada. Univ Lund, Dept Math Phys, S-22100 Lund, Sweden. Florida State Univ, Dept Phys, Tallahassee, FL 32306 USA. RP Galindo-Uribarri, A (reprint author), Oak Ridge Natl Lab, Div Phys, POB 2008, Oak Ridge, TN 37831 USA. RI radford, David/A-3928-2015 NR 16 TC 29 Z9 29 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 12 PY 1998 VL 422 IS 1-4 BP 45 EP 51 DI 10.1016/S0370-2693(97)01541-4 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK629 UT WOS:000073344400008 ER PT J AU Agakichiev, G Baur, R Braun-Munzinger, P Ceretto, F Drees, A Esumi, S Faschingbauer, U Fraenkel, Z Fuchs, C Gatti, E Glassel, P de los Heros, CP Holl, P Jung, C Lenkeit, B Messer, M Panebrattsev, Y Pfeiffer, A Rak, J Ravinovich, I Razin, S Rehak, P Richter, M Sampietro, M Saveljic, N Schukraft, J Shimansky, S Seipp, W Socol, E Specht, HJ Stachel, J Tel-Zur, G Tserruya, I Ullrich, T Voigt, C Weber, C Wessels, JP Wienold, T Wurm, JP Yurevich, V AF Agakichiev, G Baur, R Braun-Munzinger, P Ceretto, F Drees, A Esumi, S Faschingbauer, U Fraenkel, Z Fuchs, C Gatti, E Glassel, P de los Heros, CP Holl, P Jung, C Lenkeit, B Messer, M Panebrattsev, Y Pfeiffer, A Rak, J Ravinovich, I Razin, S Rehak, P Richter, M Sampietro, M Saveljic, N Schukraft, J Shimansky, S Seipp, W Socol, E Specht, HJ Stachel, J Tel-Zur, G Tserruya, I Ullrich, T Voigt, C Weber, C Wessels, JP Wienold, T Wurm, JP Yurevich, V CA CERES Collaboration TI Low-mass e(+)e(-) pair production in 158 A GeV Pb-Au collisions at the CERN SPS, its dependence on multiplicity and transverse momentum SO PHYSICS LETTERS B LA English DT Article ID HEAVY-ION COLLISIONS; SUPER PROTON SYNCHROTRON; DILEPTON PRODUCTION AB We report a measurement of low-mass electron pairs observed in 158 GeV/nucleon Pb-Au collisions. The pair yield integrated over the range of invariant masses 0.2 less than or equal to m less than or equal to 2.0 GeV/c(2) is enhanced by a factor of 3.5 +/- 0.4 (stat) +/- 0.9 (syst) over the expectation from neutral meson decays. As observed previously in S-Au collisions, the enhancement is most pronounced in the invariant-mass region 300-700 MeV/c(2). For Pb-Au we find evidence for a strong increase of the enhancement with centrality. In addition, we show that the enhancement covers a wide range in transverse momentum, but is largest at the lowest observed p(perpendicular to). (C) 1998 Published by Elsevier Science B.V. C1 JINR, Dubna, Russia. Univ Heidelberg, D-6900 Heidelberg, Germany. GSI Darmstadt, D-6100 Darmstadt, Germany. Max Planck Inst Kernphys, D-69117 Heidelberg, Germany. Weizmann Inst Sci, IL-76100 Rehovot, Israel. Politecn Milan, I-20133 Milan, Italy. Brookhaven Natl Lab, Upton, NY 11973 USA. CERN, Geneva, Switzerland. RP Agakichiev, G (reprint author), JINR, Dubna, Russia. RI Sampietro, Marco/A-3732-2016; OI Sampietro, Marco/0000-0003-4825-9612; Perez de los Heros, Carlos/0000-0002-2084-5866 NR 28 TC 237 Z9 238 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 12 PY 1998 VL 422 IS 1-4 BP 405 EP 412 DI 10.1016/S0370-2693(98)00083-5 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK629 UT WOS:000073344400052 ER PT J AU Henderson, MA AF Henderson, MA TI Evidence for bicarbonate formation on vacuum annealed TiO2(110) resulting from a precursor-mediated interaction between CO2 and H2O SO SURFACE SCIENCE LA English DT Article DE carbon dioxide; chemisorption; electron energy loss spectroscopy (EELS); secondary ion mass spectrometry (SIMS); single crystal surfaces; surface chemical reaction; thermal desorption spectroscopy (TDS); titanium dioxide; water ID MOLECULAR-ORBITAL CALCULATIONS; CARBON DIOXIDE SYSTEM; MICROWAVE SPECTROSCOPY; ELECTRONIC-STRUCTURE; ANATASE PROPERTIES; CRYSTAL-SURFACES; BASIC PROPERTIES; OXIDE SURFACES; METAL-OXIDES; INFRA-RED AB The reaction of CO2 and H2O to form bicarbonate (HCO3-) was examined on the nearly perfect and vacuum annealed surfaces of TiO2 (110) with temperature programmed desorption (TPD), static secondary ion mass spectrometry (SSIMS) and high resolution electron energy loss spectrometry (HREELS). The vacuum annealed TiO2 (110) surface possesses oxygen vacancy sires that are manifested in electronic EELS by a loss feature at 0.75 V. These oxygen vacancy sites bind CO2 only slightly more strongly (TPD peak at 166 K) than do the five-coordinated Ti4+ sites (TPD peak ar 137 K) typical of the nearly perfect TiO2 (110) surface. Vibrational HREELS indicates that CO2 is linearly bound at the latter sites with a v(a) (OCO) frequency similar to the gas phase value. In contrast, oxygen vacancies dissociate H2O to bridging OH groups which recombine to liberate H2O in TPD at 490 K. No evidence for a reaction between CO2 and H2O is detected on the nearly perfect surface. In sequentially dosed experiments on the vacuum annealed surface at 110 K, CO2 adsorption is blocked by the presence of preadsorbed H2O, adsorbed CO2 is displaced by postdosed H2O, and there is little or no evidence for bicarbonate formation in either case. How ever, when CO2 and H2O are simultaneously dosed. a new CO2 TPD state is observed at 213 K, and the 166 K state associated with CO2 at the vacancies is absent. SSIMS was used to tentatively assign the 213 K CO2 TPD state to a bicarbonate species. The 213 K CO2 TPD state is nor formed if the vacancy sites are filled with OH groups prior to simultaneous CO2+H2O exposure. Sticking coefficient measurements suggest that CO2 adsorption at 110 K is precursor-mediated, as is known to be the case for H2O adsorption on TiO2(110). A model explaining the circumstances under which the proposed bicarbonate species is formed involves the surface catalyzed conversion of a precursor-bound H2O-CO2 van der Waals complex to carbonic acid. which then reacts at unoccupied oxygen vacancies to generate bicarbonate. but falls apart to CO2 and H2O in the absence of these sites. This model is consistent with the conditions under which bicarbonate is formed on powdered TiO2, and is similar to the mechanism by which water catalyzes carbonic acid Formation in aqueous solution. (C) 1998 Elsevier Science B.V. C1 Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Henderson, MA (reprint author), Pacific NW Lab, Environm Mol Sci Lab, POB 999,MS K8-93, Richland, WA 99352 USA. EM ma_henderson@pnl.gov NR 65 TC 149 Z9 149 U1 7 U2 65 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0039-6028 J9 SURF SCI JI Surf. Sci. PD MAR 12 PY 1998 VL 400 IS 1-3 BP 203 EP 219 DI 10.1016/S0039-6028(97)00863-7 PG 17 WC Chemistry, Physical; Physics, Condensed Matter SC Chemistry; Physics GA ZJ688 UT WOS:000073242500021 ER PT J AU Driggers, EM Cho, HS Liu, CW Katzka, CP Braisted, AC Ulrich, HD Wemmer, DE Schultz, PG AF Driggers, EM Cho, HS Liu, CW Katzka, CP Braisted, AC Ulrich, HD Wemmer, DE Schultz, PG TI Mechanistic studies of an antibody-catalyzed pericyclic rearrangement SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID OXY-COPE REARRANGEMENT; DIELS-ALDER REACTION; CLAISEN REARRANGEMENT; SUBSTITUENT AB We report NMR and kinetic studies of antibody AZ-28, which was generated against the diaryl-substituted cyclohexanol derivative 3 and catalyzes the oxy-Cope rearrangement of the corresponding hexadiene 1 to aldehyde 2 (Braisted, A. C., Schultz, P. G. J. Ant. Chem. Sec. 1994, 116, 2211-2212). Conformational studies of free substrate and the antibody-substrate complex using transferred-NOE experiments demonstrate that the antibody binds the substrate in a cyclic conformation, consistent with the chair-like geometry of 3. In contrast, free substrate adopts an extended conformation in Solution. In spite of the conformational restriction of the bound substrate revealed by NMR, the temperature dependence of the reaction indicates that the antibody functions primarily by lowering Delta H double dagger, offsetting a decrease in Delta S double dagger; the values of Delta H double dagger and Delta S double dagger are 15.4 +/- 2.4 kcal/mol and -23 +/- 8 cal/mol K, respectively. A secondary kinetic isotope effect (k(cat)H/k(cat)D) of 0.61 +/- 0.1 was measured for substrate 23 in which both allylic termini are dideuterated, indicating that the chemical rearrangement step is wholly or partially rate limiting under saturating conditions. The magnitude of this secondary isotope effect is consistent with a significant degree of bond formation between C1 and C6 of the substrate in the transition state. These results, together with the recently reported three-dimensional crystal structure for the antibody-hapten 3 complex (Ulrich, H.; Mundroff, E.; Santarsiero, B. D.; Driggers, E. M.; Stevens, R. C.; Schultz, P. G. Nature 1997, 389; 271-275), provide a detailed mechanistic model for this antibody-catalyzed reaction. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Struct Biol, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RP Wemmer, DE (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Struct Biol, Berkeley, CA 94720 USA. NR 39 TC 22 Z9 22 U1 1 U2 6 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 11 PY 1998 VL 120 IS 9 BP 1945 EP 1958 DI 10.1021/ja962933u PG 14 WC Chemistry, Multidisciplinary SC Chemistry GA ZB703 UT WOS:000072499100001 ER PT J AU Truelove, JK Klein, RI McKee, CF Holliman, JH Howell, LH Greenough, JA Woods, DT AF Truelove, JK Klein, RI McKee, CF Holliman, JH Howell, LH Greenough, JA Woods, DT TI Self-gravitational hydrodynamics with three-dimensional adaptive mesh refinement: Methodology and applications to molecular cloud collapse and fragmentation SO ASTROPHYSICAL JOURNAL LA English DT Article DE gravitation; hydrodynamics; ISM, clouds; methods, numerical; stars, formation ID HYPERBOLIC CONSERVATION-LAWS; ORDER GODUNOV METHODS; PROTOSTELLAR HYDRODYNAMICS; INTERSTELLAR CLOUDS; SIMULATIONS; ACCRETION; SYSTEMS; CORES; STARS; DISKS AB We describe a new code for numerical solution of three-dimensional self-gravitational hydrodynamics problems. This code utilizes the technique of local adaptive mesh refinement (AMR), employing multiple grids at multiple levels of resolution and automatically and dynamically adding and removing these grids as necessary to maintain adequate resolution. This technology allows solution of problems that would be prohibitively expensive with a code using fixed resolution, and it is more versatile and efficient than competing methods of achieving variable resolution. In particular, we apply this technique to simulate the collapse and fragmentation of a molecular cloud, a key step in star formation. The simulation involves many orders of magnitude of variation in length scale as fragments form at positions that are not a priori discernible from general initial conditions. In this paper, we describe the methodology behind this new code and present several illustrative applications. The criterion that guides the degree of adaptive mesh refinement is critical to the success of the scheme, and, for the isothermal problems considered here, we employ the Jeans condition for this purpose. By maintaining resolution finer than the local Jeans length, we set new benchmarks of accuracy by which to measure other codes on each problem we consider, including the uniform collapse of a finite pressured cloud. We find that the uniformly rotating, spherical clouds treated here first collapse to disks in the equatorial plane and then, in the presence of applied perturbations, form filamentary singularities that do not fragment while isothermal. Our results provide numerical confirmation of recent work by Inutsuka & Miyama on this scenario of isothermal filament formation. C1 Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Lawrence Livermore Natl Lab, Inst Geophys & Planetary Phys, Livermore, CA 94550 USA. Univ Calif Berkeley, Space Sci Lab, Berkeley, CA 94720 USA. Lawrence Berkeley Lab, Ctr Computat Sci & Engn, Berkeley, CA 94720 USA. RP Truelove, JK (reprint author), Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA. NR 60 TC 187 Z9 187 U1 0 U2 1 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 1998 VL 495 IS 2 BP 821 EP 852 DI 10.1086/305329 PN 1 PG 32 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZD699 UT WOS:000072714200030 ER PT J AU Mezzacappa, A Calder, AC Bruenn, SW Blondin, JM Guidry, MW Strayer, MR Umar, AS AF Mezzacappa, A Calder, AC Bruenn, SW Blondin, JM Guidry, MW Strayer, MR Umar, AS TI An investigation of neutrino-driven convection and the core collapse supernova mechanism using multigroup neutrino transport SO ASTROPHYSICAL JOURNAL LA English DT Article DE convection; elementary particles; stars, interiors; supernovae, general ID GAMMA-RAY LINE; DIFFUSIVE INSTABILITIES; II SUPERNOVA; SN 1987A; SN-1987A; EXPLOSIONS; EMISSION; SIMULATIONS; RESOLUTION; ACCRETION AB We investigate neutrino-driven convection in core collapse supernovae and its ramifications for the explosion mechanism. We begin with a postbounce model that is optimistic in two important respects: (1) we begin with a 15 M. precollapse model, which is representative of the class of stars with compact iron cores; (2) we implement Newtonian gravity. Our precollapse model is evolved through core collapse and bounce in one dimension using multigroup (neutrino energy-dependent) flux-limited diffusion (MGFLD) neutrino transport and Newtonian Lagrangian hydrodynamics, providing realistic initial conditions for the postbounce convection and evolution. Our two-dimensional simulation begins at 12 ms after bounce and proceeds for 500 ms. We couple two-dimensional piecewise parabolic method (PPM) hydrodynamics to precalculated one-dimensional MGFLD neutrino transport. (The neutrino distributions used for matter heating and deleptonization in our two-dimensional run are obtained from an accompanying one-dimensional simulation. The accuracy of this approximation is assessed.) For the moment, we sacrifice dimensionality for realism in other aspects of our neutrino transport. MGFLD is an implementation of neutrino transport that simultaneously (1) is multigroup and (2) simulates with sufficient realism the transport of neutrinos in opaque, semitransparent, and transparent regions. Both are crucial to the accurate determination of postshock neutrino heating, which sensitively depends on the luminosities, spectra, and flux factors of the electron neutrinos and antineutrinos emerging from their respective neutrinospheres. By 137 ms after bounce, we see neutrino-driven convection rapidly developing beneath the shock. By 212 ms after bounce, this convection becomes large scale, characterized by higher entropy, expanding upflows and lower entropy, denser, finger-like downflows. The upflows reach the shock and distort it from sphericity. The radial convection velocities at this time become supersonic just below the shock, reaching magnitudes in excess of 10(9) cm s(-1). Eventually, however, the shock recedes to smaller radii, and at similar to 500 ms after bounce there is no evidence in our simulation of an explosion or of a developing explosion. Our angle-averaged density, entropy, electron fraction, and radial velocity profiles in our two-dimensional model agree well with their counterparts in our accompanying one-dimensional MGFLD run above and below the neutrino-driven convection region. In the convection region, the one-dimensional and angle-averaged profiles differ somewhat because (1) convection tends to flatten the density, entropy, and electron fraction profiles, and (2) the shock radius is boosted somewhat by convection. However, the differences are not significant, indicating that, while vigorous, neutrino-driven convection in our model does not have a significant impact on the overall shock dynamics. The differences between our results and those of other groups are considered. These most likely result from differences in (1) numerical hydrodynamics methods; (2) initial postbounce models, and, most important; (3) neutrino transport approximations. We have compared our neutrino luminosities, rms energies, and inverse flux factors with those from the exploding models of other groups. Above all, we find that the neutrino rms energies computed by our multigroup (MGFLD) transport are significantly lower than the values obtained by Burrows and coworkers, who specified their neutrino spectra by tying the neutrino temperature to the matter temperature at the neutrinosphere and by choosing the neutrino degeneracy parameter arbitrarily, and by Herant and coworkers in their transport scheme, which (1) is gray and (2) patches together optically thick and thin regions. The most dramatic difference between our results and those of Janka and Muller is exhibited by the difference in the net cooling rate below the gain radii: Our rate is 2-3 times greater during the critical 50-100 ms after bounce. We have computed the mass and internal energy in the gain region as a function of time. Up to similar to 150 ms after bounce, we find that both increase as a result of the increasing gain region volume, as the gain and shock radii diverge. However, at all subsequent times, we find that the mass and internal energy in the gain region decrease with time in accordance with the density falloff in the preshock region and with the how of matter into the gain region at the shock and out of the gain region at the gain radius. Therefore, we see no evidence in the simulations presented here that neutrino-driven convection leads to mass and energy accumulation in the gain region. We have compared our one-and two-dimensional densities, temperatures, and electron fractions in the region below the electron neutrino and antineutrino gain radii, above which the neutrino luminosities are essentially constant (i.e., the neutrino sources are entirely enclosed), in an effort to assess how spherically symmetric our neutrino sources remain during our two-dimensional evolution, and therefore, in an effort to assess our use of precalculated one-dimensional MGFLD neutrino distributions in calculating the matter heating and deleptonization. We find no difference below the neutrinosphere radii. Between the neutrinosphere and gain radii we find no differences with obvious ramifications for the supernova outcome. We note that the interplay between neutrino transport and convection below the neutrinospheres is a delicate matter and is discussed at greater length in another paper (Mezzacappa and coworkers). However, the results presented therein do support our use of precalculated one-dimensional MGFLD in the present context. Failure in our "optimistic" 15 M. Newtonian model leads us to conclude that it is unlikely, at least in our approximation, that neutrino-driven convection will lead to explosions for more massive stars with fatter iron cores or in cases in which general relativity is included. C1 Oak Ridge Natl Lab, Theoret & Computat Phys Grp, Oak Ridge, TN 37831 USA. Univ Tennessee, Dept Phys & Astron, Knoxville, TN 37996 USA. Vanderbilt Univ, Dept Phys & Astron, Nashville, TN 37235 USA. Florida Atlantic Univ, Dept Phys, Boca Raton, FL 33431 USA. N Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA. RP Mezzacappa, A (reprint author), Oak Ridge Natl Lab, Theoret & Computat Phys Grp, Oak Ridge, TN 37831 USA. RI Calder, Alan/E-5348-2011; Umar, Ahmet/J-4125-2013; Mezzacappa, Anthony/B-3163-2017 OI Umar, Ahmet/0000-0002-9267-5253; Mezzacappa, Anthony/0000-0001-9816-9741 NR 74 TC 136 Z9 136 U1 1 U2 1 PU UNIV CHICAGO PRESS PI CHICAGO PA 5801 S ELLIS AVENUE, CHICAGO, IL 60637 USA SN 0004-637X J9 ASTROPHYS J JI Astrophys. J. PD MAR 10 PY 1998 VL 495 IS 2 BP 911 EP + DI 10.1086/305338 PN 1 PG 20 WC Astronomy & Astrophysics SC Astronomy & Astrophysics GA ZD699 UT WOS:000072714200035 ER PT J AU Qiu, J Gao, W Lesht, BM AF Qiu, J Gao, W Lesht, BM TI Inverting optical reflectance to estimate surface properties of vegetation canopies SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article ID ESTIMATING AGRONOMIC VARIABLES; BIDIRECTIONAL-REFLECTANCE; TALLGRASS PRAIRIE; PHYSICAL MODEL; SUITS MODEL; INVERSION; PHOTOSYNTHESIS; EXCHANGE; TRANSPIRATION; RADIATION AB An inversion method using a simple bidirectional reflectance model and data on optical reflectances remotely-sensed from satellites has been improved to derive surface properties such as the leaf area index (LAI). Such properties are important in deriving the resistance of the vegetative canopy to uptake of gaseous trace chemicals from the atmosphere and in the study of radiation transfer processes. We found that a multi-pass retrieval technique can greatly improve a model's ability to retrieve surface properties. Because the sensitivity of the model inversion to initial values is an important issue that depends on (1) the partial derivative of reflectance with respect to each parameters to be retrieved (partial derivative R/partial derivative x) and (2) the degree of independence among model parameters, we investigated the issue with synthetic data constructed by a bidirectional reflectance model. The results revealed that, although the surface optical properties are mostly independent of each other, their initial values did have some effect on the retrieved value of the LAI, with the worse case caused by leaf angle distribution index, n, at close-to-nadir solar and view zenith angles of the reflectance data. At near-nadir angles, n and LAI were strongly correlated, and their retrieval was not unique. When applied to satellite remote sensing data obtained with the advanced very-high-resolution radiometer (AVHRR), the model-retrieved seasonal variation of surface properties agreed reasonably well with independent ground measurements made in the First International Satellite Land-Surface Climatology Project (ISLSCP) Field Experiment (FIFE) campaign. Application to Landsat data to retrieve spatial variation was less successful, largely because of the close-to-nadir solar and view zenith angles in the data. C1 Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. RP Qiu, J (reprint author), Argonne Natl Lab, Div Environm Res, Argonne, IL 60439 USA. NR 20 TC 17 Z9 19 U1 0 U2 4 PU TAYLOR & FRANCIS LTD PI LONDON PA ONE GUNPOWDER SQUARE, LONDON EC4A 3DE, ENGLAND SN 0143-1161 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAR 10 PY 1998 VL 19 IS 4 BP 641 EP 656 DI 10.1080/014311698215900 PG 16 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA ZB310 UT WOS:000072458200006 ER PT J AU Stallard, BR Motomatsu, SE AF Stallard, BR Motomatsu, SE TI Regularization of an isolated rectangular target viewed with an array of square pixels SO INTERNATIONAL JOURNAL OF REMOTE SENSING LA English DT Article AB In remote sensing, a target generally has a random position and orientation with respect to the array of image pixels. We derive a simple analytic expression for the expectation value of the area of a rectangular target relative to the area of a square image pixel containing the target's centre point. The analytic result applies when the sides of the target and image pixel are parallel. We then consider the possibility of a random orientation of the target using a more general digital approach. Interestingly, we find that the analytic expression (ignoring orientational averaging) is quite adequate for practical applications. C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. RP Stallard, BR (reprint author), Sandia Natl Labs, POB 5800,MS 0980, Albuquerque, NM 87185 USA. NR 10 TC 1 Z9 1 U1 0 U2 0 PU TAYLOR & FRANCIS LTD PI ABINGDON PA 4 PARK SQUARE, MILTON PARK, ABINGDON OX14 4RN, OXON, ENGLAND SN 0143-1161 EI 1366-5901 J9 INT J REMOTE SENS JI Int. J. Remote Sens. PD MAR 10 PY 1998 VL 19 IS 4 BP 783 EP 787 DI 10.1080/014311698216017 PG 5 WC Remote Sensing; Imaging Science & Photographic Technology SC Remote Sensing; Imaging Science & Photographic Technology GA ZB310 UT WOS:000072458200017 ER PT J AU Brown, S Caprihan, A Hardy, R AF Brown, S Caprihan, A Hardy, R TI Experimental observation of fluid flow channels in a single fracture SO JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH LA English DT Article ID TRANSPORT-PROPERTIES; CONFINING PRESSURE; SURFACE-ROUGHNESS; SOLUTE TRANSPORT; ROCK; PERMEABILITY; MODEL AB A method for obtaining precise replicas of real fracture surfaces using transparent epoxy resins was developed, allowing detailed study of fluid flow paths within a fracture plane. A natural rock fracture was collected from the field and prepared for study. Silicon rubber molds of the fracture surfaces were used to make a transparent epoxy replica of the original fracture. Clear and dyed water were injected into the fracture pore space allowing examination of the flow field. Digitized optical images were used to observe wetting, saturated flow, and drying of the specimen. Nuclear magnetic resonance imaging was used for quantitative measurements of flow velocity. Both video imaging and nuclear magnetic resonance imaging techniques show distinct and strong channeling of the flow at the submillimeter to several-centimeter scale. Each phenomenon, including wetting, drying, dye transport, and velocity channeling, has its own distinct geometric structure and scale. We find that fluid velocities measured simultaneously at various locations in the fracture plane during steady state flow range over several orders of magnitude, with the maximum velocity a factor of 5 higher than the mean velocity. This suggests that flow channeling in fractured rock can cause the breakthrough velocity of contaminants to far exceed the mean flow. C1 New England Res, White River Junction, VT 05001 USA. Sandia Natl Labs, Geomech Dept, Albuquerque, NM 87185 USA. Lovelace Resp Res Inst, Albuquerque, NM USA. RP Brown, S (reprint author), New England Res, 76 Olcott Dr, White River Junction, VT 05001 USA. EM sbrown@ner.com; acapriha@lucy.lrri.org; rdhardy@sandia.gov NR 29 TC 102 Z9 103 U1 1 U2 10 PU AMER GEOPHYSICAL UNION PI WASHINGTON PA 2000 FLORIDA AVE NW, WASHINGTON, DC 20009 USA SN 2169-9313 EI 2169-9356 J9 J GEOPHYS RES-SOL EA JI J. Geophys. Res.-Solid Earth PD MAR 10 PY 1998 VL 103 IS B3 BP 5125 EP 5132 DI 10.1029/97JB03542 PG 8 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA ZB383 UT WOS:000072466700016 ER PT J AU Diko, P Goretta, KC AF Diko, P Goretta, KC TI Macroscopic shape change of melt-processed YBa2Cu3Ox/Y2BaCuO5 bulk superconductors SO PHYSICA C LA English DT Article DE liquid transport; edge melt distribution; superconductors ID TEXTURED YBA2CU3O7-X; GROWTH; Y2BACUO5; MICROSTRUCTURE; PARTICLES; OXIDES; SOLIDIFICATION; SEGREGATION; MORPHOLOGY; MECHANISM AB A macroscopic change in the shape of five-domain melt-processed YBa2Cu3Ox/Y2BaCuO5 bulk superconductors is reported and explained. The change, a distortion from circular cross-section, is attributed to liquid transport from a slower growth front in an a-axis direction to a faster growth front in a c-axis direction at the edge between the a- and c-growth fronts, a phenomenon that we call the edge melt distribution (EMD) effect. Formation of bands of higher Y2BaCuO5 particle density along the a/c growth boundaries, which nearly coincide with {110}-type planes, is explained by the EMD effect. (C) 1998 Elsevier Science B.V. C1 Slovak Acad Sci, Inst Expt Phys, Kosice 04353, Slovakia. Argonne Natl Lab, Div Energy Technol, Argonne, IL 60439 USA. RP Diko, P (reprint author), Slovak Acad Sci, Inst Expt Phys, Watsonova 47, Kosice 04353, Slovakia. NR 17 TC 6 Z9 6 U1 0 U2 1 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0921-4534 J9 PHYSICA C JI Physica C PD MAR 10 PY 1998 VL 297 IS 3-4 BP 211 EP 215 DI 10.1016/S0921-4534(97)01871-6 PG 5 WC Physics, Applied SC Physics GA ZM548 UT WOS:000073551200006 ER PT J AU Ruppert, S Fliedner, MM Zandt, G AF Ruppert, S Fliedner, MM Zandt, G TI Thin crust and active upper mantle beneath the Southern Sierra Nevada in the western United States SO TECTONOPHYSICS LA English DT Article; Proceedings Paper CT 7th International Symposium on Deep Seismic Profiling of the Continents CY SEP 12-15, 1996 CL ASILOMAR, CALIFORNIA SP Stanford Univ, US Geol Survey, Nat Sci Fdn, Refract Technol Inc, Int Assoc Seismol & Phys Earths Interior, Int Lithsphere Program, Amer Assoc Petr Geologists, Soc Explorat Geophysicists DE Sierra Nevada; crustal root; seismic refraction; SSCD; upper mantle; tomography ID LITHOSPHERE BENEATH; CALIFORNIA; UPLIFT; EVOLUTION; EXTENSION; PROFILES; GRAVITY; ORIGIN; VALLEY; MODEL AB A nalysis of seismic-refraction/wide-angle reflection travel-time and seismic amplitude data collected during the 1993 Southern Sierra Nevada Continental Dynamics (SSCD) project resolves a small crustal root (40-42 km thick) centered 80 km west of the Sierran topographic crest. The SSCD experiment consisted of a west-east profile across the Sierra Nevada at approximately 36.5 degrees N and a north-south profile extending the length of Owens Valley, located eastward of the Sierran topographic crest. Two-dimensional finite-difference travel-time inversion of P-g and P-n arrivals resolves upper-crustal velocities of 6.0 to 6.4 km s(-1) within the Sierran Batholith and Basin and Range, an upper-crustal west-dipping wedge of higher velocities (6.8-7.2 km s(-1)) consistent with ophiolitic material underlying the Great Valley sedimentary sequence, and higher velocities in the lower crust beneath the Basin and Range (6.8-7.0 km s(-1)) than those beneath the Sierran Batholith (6.6 km s(-1)). Low average P-n velocities (7.6-7.9 km s(-1)) and a laminated transitional Moho imaged beneath the Sierran Batholith also differ from the higher P-n velocities (7.9-8.0 km s(-1)) and sharp first-order Moho observed beneath the Basin and Range. The crust decreases in thickness both westward of the root to 28-34 km beneath the Great Valley and eastward to 35 km beneath the highest Sierran topography and decreases further to 27-30 km beneath the Basin and Range. Crustal thickness also appears to increase southeast to northwest from 29-30 km beneath the Garlock Fault in the south to 38-40 km beneath the north end of Chalfant Valley. Juxtaposition of the crustal model with previous P-wave tomography models of the southernmost Sierra Nevada upper-mantle reveal that the thickest Sierran crust on the west-east profile overlies a pronounced upper-mantle high-velocity anomaly (+5%), whereas the region of laminated Moho overlies a flanking upper-mantle low-velocity region (-3%). The upper-mantle velocity anomalies, relatively low P-n, and relatively flat Moho, observed beneath the Sierran crest suggest that the recent uplift of the Sierra Nevada is due to asthenospheric flow and/or lithospheric thinning beneath the southeastern Sierra Nevada and Basin and Range. (C) 1998 Elsevier Science B.V. All rights reserved. C1 Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Stanford Univ, Dept Geophys, Stanford, CA 94305 USA. Univ Arizona, Dept Geosci, Tucson, AZ 85721 USA. RP Ruppert, S (reprint author), Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. EM ruppert@s157.es.llnl.gov NR 50 TC 69 Z9 72 U1 0 U2 2 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0040-1951 J9 TECTONOPHYSICS JI Tectonophysics PD MAR 10 PY 1998 VL 286 IS 1-4 BP 237 EP 252 DI 10.1016/S0040-1951(97)00268-0 PG 16 WC Geochemistry & Geophysics SC Geochemistry & Geophysics GA ZF890 UT WOS:000072943500020 ER PT J AU Tan, HH Williams, JS Zou, J Cockayne, DJH Pearton, SJ Zolper, JC Stall, RA AF Tan, HH Williams, JS Zou, J Cockayne, DJH Pearton, SJ Zolper, JC Stall, RA TI Annealing of ion implanted gallium nitride SO APPLIED PHYSICS LETTERS LA English DT Article ID GAN; DIODES AB In this paper, we examine Si and Te ion implant damage removal in GaN as a function of implantation dose, and implantation and annealing temperature. Transmission electron microscopy shows that amorphous layers, which can result from high-dose implantation, recrystallize between 800 and 1100 degrees C to very defective polycrystalline material. Lower-dose implants (down to 5 x 10(13) cm(-2)), which are not amorphous but defective after implantation, also anneal poorly up to 1100 degrees C, leaving a coarse network of extended defects. Despite such disorder, a high fraction of Te is found to be substitutional in GaN both following implantation and after annealing. Furthermore, although elevated-temperature implants result in less disorder after implantation, this damage is also impossible to anneal out completely by 1100 degrees C. The implications of this study are that considerably higher annealing temperatures will be needed to remove damage for optimum electrical properties. (C) 1998 American Institute of Physics. [S0003-6951(98)00710-4]. C1 Australian Natl Univ, Res Sch Phys Sci & Engn, Dept Elect Mat Engn, Canberra, ACT 0200, Australia. Univ Sydney, Electron Microscope Unit, Sydney, NSW 2006, Australia. Univ Sydney, Australian Key Ctr Microscopy & Microanal, Sydney, NSW 2006, Australia. Univ Florida, Dept Mat Sci & Engn, Gainesville, FL 32611 USA. Sandia Natl Labs, Albuquerque, NM 87185 USA. EMCORE Corp, Somerset, NJ 08873 USA. RP Tan, HH (reprint author), Australian Natl Univ, Res Sch Phys Sci & Engn, Dept Elect Mat Engn, Canberra, ACT 0200, Australia. EM hoe109@rsphyl.anu.edu.au RI Zou, Jin/B-3183-2009; Tan, Hark Hoe/M-1148-2015 OI Zou, Jin/0000-0001-9435-8043; Tan, Hark Hoe/0000-0002-7816-537X NR 19 TC 65 Z9 66 U1 0 U2 7 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0003-6951 J9 APPL PHYS LETT JI Appl. Phys. Lett. PD MAR 9 PY 1998 VL 72 IS 10 BP 1190 EP 1192 DI 10.1063/1.121030 PG 3 WC Physics, Applied SC Physics GA ZA514 UT WOS:000072370900021 ER PT J AU Harrison, WTA Liu, LM Jacobson, AJ Vogt, T AF Harrison, WTA Liu, LM Jacobson, AJ Vogt, T TI SrHg2O2Cl2, the first strontium mercury oxychloride. Crystal structure determination by ab initio powder methods SO INORGANIC CHEMISTRY LA English DT Article ID DIFFRACTION AB The new phase SrHg2O2Cl2 includes an unusual T-shaped HgO3 grouping as part of infinite [Hg2O2]-infinity sheets. The structure of SrHg2O2Cl2 was determined by ab initio methods from laboratory X-ray powder data and optimized by a joint Rietveld refinement against X-ray and neutron data. C1 Univ Western Australia, Dept Chem, Nedlands, WA 6907, Australia. Univ Houston, Dept Chem, Houston, TX 77204 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Harrison, WTA (reprint author), Univ Western Australia, Dept Chem, Nedlands, WA 6907, Australia. RI Vogt, Thomas /A-1562-2011 OI Vogt, Thomas /0000-0002-4731-2787 NR 9 TC 6 Z9 6 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 9 PY 1998 VL 37 IS 5 BP 834 EP 835 DI 10.1021/ic9706008 PG 2 WC Chemistry, Inorganic & Nuclear SC Chemistry GA ZC376 UT WOS:000072571700001 ER PT J AU Andersen, AMK Norby, P Hanson, JC Vogt, T AF Andersen, AMK Norby, P Hanson, JC Vogt, T TI Preparation and characterization of a new 3-dimensional zirconium hydrogen phosphate, tau-Zr(HPO4)(2). Determination of the complete crystal structure combining synchrotron x-ray single-crystal diffraction and neutron powder diffraction SO INORGANIC CHEMISTRY LA English DT Article ID REFINEMENT; FORM AB A new 3-dimensional zirconium hydrogen phosphate. tau-Zr(HPO4)(2), was prepared by hydrothermal syntheses. The preparation, characterization, and determination of the crystal structure of this new material are reported. The structure was solved from single-crystal synchrotron diffraction on a 25 x 25 x 50 mu m crystal. The position of the hydrogen atom was found using high-resolution neutron powder diffraction data: The unit cell is tetragonal, space group l4(1)cd (No. 110), with lattice parameters a = 11.259(1) Angstrom, c = 10.764(1) Angstrom, and Z = 8. The structure can be described as a 3-dimensional framework built from ZrO6 octahedra bound together by hydrogen phosphate groups (PO3(OH)). The OH groups form a hydrogen-bonded spiral along the 4(1) axes, with each hydrogen phosphate both donating and accepting hydrogen bonds. The thermal transformations of tau-Zr(HPO4)(2) were studied using in-situ temperature-resolved powder diffraction experiments. Hereby the existence of two new phases was discovered. The new phases have been indexed and the unit cell parameters are as follows, intermediate I: a = 8.172(1), b = 7.691(1), and c = 10.794(2) Angstrom. Intermediate II: a = 8.283(2), b = 6.620(2), and c = 10.643(2) Angstrom. C1 Odense Univ, Dept Chem, DK-5230 Odense M, Denmark. Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. Brookhaven Natl Lab, Dept Phys, Upton, NY 11973 USA. RP Andersen, AMK (reprint author), Odense Univ, Dept Chem, Campusvej 55, DK-5230 Odense M, Denmark. RI Hanson, jonathan/E-3517-2010; Vogt, Thomas /A-1562-2011; Norby, Poul/B-9047-2014 OI Vogt, Thomas /0000-0002-4731-2787; Norby, Poul/0000-0002-2590-7050 NR 24 TC 21 Z9 22 U1 0 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 9 PY 1998 VL 37 IS 5 BP 876 EP 881 PG 6 WC Chemistry, Inorganic & Nuclear SC Chemistry GA ZC376 UT WOS:000072571700009 ER PT J AU Sun, J Wishart, JF AF Sun, J Wishart, JF TI Intramolecular electron transfer in tetraammine(L)ruthenium(III)-modified manganocytochromes c SO INORGANIC CHEMISTRY LA English DT Article ID MODIFIED CYTOCHROME-C; TRANSFER KINETICS; PROTEINS; RUTHENIUM(II); DERIVATIVES; DEPENDENCE; CHEMISTRY; RATES AB Manganese-substituted horse heart cytochrome c was modified at histidine-33 with the ruthenium complexes trans-(NH3)(4)(L)Ru-His33, where L=NH3, pyridine, or isonicotinamide. Manganese(II)-to-ruthenium(III) intramolecular electron-transfer rates were measured by pulse radiolysis as functions of concentration and temperature to obtain intramolecular and intermolecular electron-transfer rate constants and activation parameters. C1 Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RP Wishart, JF (reprint author), Brookhaven Natl Lab, Dept Chem, Upton, NY 11973 USA. RI Wishart, James/L-6303-2013 OI Wishart, James/0000-0002-0488-7636 NR 26 TC 2 Z9 2 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0020-1669 J9 INORG CHEM JI Inorg. Chem. PD MAR 9 PY 1998 VL 37 IS 5 BP 1124 EP 1126 DI 10.1021/ic971169p PG 3 WC Chemistry, Inorganic & Nuclear SC Chemistry GA ZC376 UT WOS:000072571700041 ER PT J AU Ahuja, R Eriksson, O Wills, JM Johansson, B AF Ahuja, R Eriksson, O Wills, JM Johansson, B TI Theoretical high-pressure studies of caesium hydride SO JOURNAL OF PHYSICS-CONDENSED MATTER LA English DT Letter ID CRYSTAL-STRUCTURE; BRILLOUIN-ZONE; SPECIAL POINTS; TRANSITION; EQUATION; SYSTEMS; SOLIDS; STATE; BAND; CSI AB We have investigated the alkali hydrides theoretically under high compressions by means of first-principles self-consistent total-energy calculations within the local-density approximation using the full-potential linear-muffin-tin-orbital (FPLMTO) method. Our results confirm the recent high-pressure experimental observations of crystallographic phase transformations in CsH (Ghandehari K, Luo H, Ruoff A L, Trail S S and DiSalvo F J 1995 Phys. Rev. Lett. 74 2264). The calculated transition pressures for the occurrence of the CsCl and CrB crystal structures as well as the associated theoretical volume changes agree with the experimental data. We also predict a similar high-pressure behaviour for RbH and KH but not for NaH and LiH. C1 Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, S-75121 Uppsala, Sweden. Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Uppsala Univ, Dept Phys, Condensed Matter Theory Grp, Box 530, S-75121 Uppsala, Sweden. RI Eriksson, Olle/E-3265-2014 OI Eriksson, Olle/0000-0001-5111-1374 NR 26 TC 6 Z9 8 U1 0 U2 3 PU IOP PUBLISHING LTD PI BRISTOL PA TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND SN 0953-8984 EI 1361-648X J9 J PHYS-CONDENS MAT JI J. Phys.-Condes. Matter PD MAR 9 PY 1998 VL 10 IS 9 BP L153 EP L158 DI 10.1088/0953-8984/10/9/002 PG 6 WC Physics, Condensed Matter SC Physics GA ZB497 UT WOS:000072478500002 ER PT J AU Dorey, N Khoze, VV Mattis, MP AF Dorey, N Khoze, VV Mattis, MP TI Supersymmetry and the multi-instanton measure SO NUCLEAR PHYSICS B LA English DT Article ID YANG-MILLS THEORY; GAUGE-THEORIES; DUALITY; EQUATION; QCD AB We propose explicit formulae for the integration measure on the moduli space of charge-n ADHM multi-instantons in N = 1 and N = 2 supersymmetric gauge theories. The form of this measure is fixed by its (super)symmetries as well as the physical requirement of clustering in the limit of large spacetime separation between instantons. We test our proposals against known expressions for n less than or equal to 2. Knowledge of the measure for all n allows us to revisit, and strengthen, earlier N = 2 results, chiefly: (1) For any number of flavors N-F, we provide a closed formula for F-n, the n-instanton contribution to the Seiberg-Witten prepotential, as a finite-dimensional collective coordinate integral. This amounts to a solution, in quadratures, of the Seiberg-Witten models, without appeal to electric-magnetic duality. (2) In the conformal case N-F = 4, this means reducing to quadratures the previously unknown finite renormalization that relates the microscopic and effective coupling constants, tau(micro) and tau(eff). (3) Similar expressions are given for the 4-derivative/8-fermion term in the gradient expansion of N = 2 supersymmetric QCD. (C) 1998 Elsevier Science B.V. C1 Univ Wales, Dept Phys, Swansea SA2 8PP, W Glam, Wales. Univ Durham, Ctr Particle Theory, Dept Phys, Durham DH1 3LE, England. Univ Calif Los Alamos Natl Lab, Theoret Div T8, Los Alamos, NM 87545 USA. RP Dorey, N (reprint author), Univ Wales, Dept Phys, Swansea SA2 8PP, W Glam, Wales. OI Khoze, Valentin V/0000-0003-3006-4147 NR 36 TC 26 Z9 26 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0550-3213 J9 NUCL PHYS B JI Nucl. Phys. B PD MAR 9 PY 1998 VL 513 IS 3 BP 681 EP 708 DI 10.1016/S0550-3213(97)00747-5 PG 28 WC Physics, Particles & Fields SC Physics GA ZF728 UT WOS:000072926100008 ER PT J AU Aharonov, Y Kaufherr, T Popescu, S Reznik, B AF Aharonov, Y Kaufherr, T Popescu, S Reznik, B TI Quantum measurement backreaction and induced topological phases SO PHYSICAL REVIEW LETTERS LA English DT Article AB It is shown that a topological vector potential (Berry phase) is induced by the act of measuring angular momentum in a direction defined by a reference particle. This vector potential appears as a consequence of the backreaction due to the quantum measurement. C1 Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. Univ S Carolina, Dept Phys, Columbia, SC 29208 USA. Univ Cambridge, Isaac Newton Inst, Cambridge CB3 0HE, England. Hewlett Packard Labs, BRIMS, Bristol BS12 6QZ, Avon, England. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Aharonov, Y (reprint author), Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel. NR 6 TC 10 Z9 10 U1 1 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2023 EP 2026 DI 10.1103/PhysRevLett.80.2023 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400001 ER PT J AU Hagmann, C Kinion, D Stoeffl, W van Bibber, K Daw, E Peng, H Rosenberg, LJ LaVeigne, J Sikivie, P Sullivan, NS Tanner, DB Nezrick, F Turner, MS Moltz, DM Powell, J Golubev, NA AF Hagmann, C Kinion, D Stoeffl, W van Bibber, K Daw, E Peng, H Rosenberg, LJ LaVeigne, J Sikivie, P Sullivan, NS Tanner, DB Nezrick, F Turner, MS Moltz, DM Powell, J Golubev, NA TI Results from a high-sensitivity search for cosmic axions SO PHYSICAL REVIEW LETTERS LA English DT Article ID INVISIBLE-AXION AB We report the first results of a high-sensitivity (similar to 10(-23) W) search for light halo axions through their conversion to microwave photons. At the 90% confidence level, we exclude a Kim-Shifman-Vainshtein-Zakharov axion of mass 2.9 x 10(-6) to 3.3 X 10(-6) eV as the dark matter in the halo of our galaxy. C1 Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. MIT, Dept Phys, Cambridge, MA 02139 USA. MIT, Nucl Sci Lab, Cambridge, MA 02139 USA. Univ Florida, Dept Phys, Gainesville, FL 32611 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Chicago, Dept Astron & Astrophys, Chicago, IL 60637 USA. Univ Chicago, Dept Phys, Chicago, IL 60637 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Russian Acad Sci, Inst Nucl Res, Moscow 117312, Russia. RP Lawrence Livermore Natl Lab, 7000 East Ave, Livermore, CA 94550 USA. NR 19 TC 116 Z9 116 U1 1 U2 2 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2043 EP 2046 DI 10.1103/PhysRevLett.80.2043 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400006 ER PT J AU Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cabau, WG Cochran, J Coney, L Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmanov, D Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Knuteson, B Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Manankov, V Mao, HS Markeloff, R Marshall, T Martin, ML Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Steinbrueck, G Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cabau, WG Cochran, J Coney, L Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, MK Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hanlet, P Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Karmanov, D Karmgard, D Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, C Klyukhin, VI Knuteson, B Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D Linn, SL Linnemann, J Lipton, R Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Manankov, V Mao, HS Markeloff, R Marshall, T Martin, ML Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibben, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Para, A Park, YM Partridge, R Parua, N Paterno, M Pawlik, B Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, E Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Steinbrueck, G Stephens, RW Stevenson, ML Stewart, D Stichelbaut, F Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A TI Search for first generation scalar leptoquark pairs in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article AB We have searched for first generation scalar leptoquark (LQ) pairs in the e nu + jets channel using collider data (integral L dt approximate to 115 pb(-1)) collected by the D0 experiment at the Fermilab Tevatron during 1992-1996. The analysis yields no candidate events. We combine the results with those from the ee + jets and nu nu + jets channels to obtain 95% confidence level (C.L.) upper limits on the LQ pair production cross section as a function of mass and of beta the branching fraction to a charged lepton. Comparing with the next-to-leading order theory, we set 95% C.L. lower limits on the LQ mass of 225, 204, and 79 GeV/c(2) for beta = 1, 1/2, and 0, respectively. C1 NYU, New York, NY 10003 USA. Univ Los Andes, Bogota, Colombia. Univ Arizona, Tucson, AZ 85721 USA. Boston Univ, Boston, MA 02215 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Brown Univ, Providence, RI 02912 USA. Univ Buenos Aires, Buenos Aires, DF, Argentina. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. CINVESTAV, Mexico City 14000, DF, Mexico. Columbia Univ, New York, NY 10027 USA. Univ Delhi, Delhi 110007, India. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Illinois, Chicago, IL 60607 USA. Indiana Univ, Bloomington, IN 47405 USA. Iowa State Univ, Ames, IA 50011 USA. Korea Univ, Seoul 136701, South Korea. Kyungsung Univ, Pusan 608736, South Korea. Inst Nucl Phys, Krakow, Poland. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Louisiana Tech Univ, Ruston, LA 71272 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Moscow State Univ, Moscow, Russia. Univ Nebraska, Lincoln, NE 68588 USA. Northeastern Univ, Boston, MA 02115 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Oklahoma, Norman, OK 73019 USA. Panjab Univ, Chandigarh 160014, India. Protvino High Energy Phys Inst, Protvino 142284, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77005 USA. Univ Estado Rio de Janeiro, Rio De Janeiro, Brazil. Univ Rochester, Rochester, NY 14627 USA. Ctr Etud Saclay, Serv Phys Particules, DAPNIA, CEA, F-91191 Gif Sur Yvette, France. Seoul Natl Univ, Seoul, South Korea. SUNY Stony Brook, Stony Brook, NY 11794 USA. Tata Inst Fundamental Res, Colaba 400005, Mumbai, India. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Aihara, Hiroaki/F-3854-2010; Alves, Gilvan/C-4007-2013; Belyaev, Alexander/F-6637-2015; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Roe, Natalie/A-8798-2012; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Klyukhin, Vyacheslav/D-6850-2012; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013 OI Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Aihara, Hiroaki/0000-0002-1907-5964; Belyaev, Alexander/0000-0002-1733-4408; Dudko, Lev/0000-0002-4462-3192; Klyukhin, Vyacheslav/0000-0002-8577-6531; De, Kaushik/0000-0002-5647-4489; NR 26 TC 69 Z9 70 U1 0 U2 2 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2051 EP 2056 DI 10.1103/PhysRevLett.80.2051 PG 6 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400008 ER PT J AU Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C HOllebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Hurth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kondo, K Kongeter, A Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E KUrino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spiegel, L Spinella, F Spiropulu, M Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S AF Abe, F Akimoto, H Akopian, A Albrow, MG Amadon, A Amendolia, SR Amidei, D Antos, J Aota, S Apollinari, G Arisawa, T Asakawa, T Ashmanskas, W Atac, M Azzi-Bacchetta, P Bacchetta, N Bagdasarov, S Bailey, MW de Barbaro, P Barbaro-Galtieri, A Barnes, VE Barnett, BA Barone, M Bauer, G Baumann, T Bedeschi, F Behrends, S Belforte, S Bellettini, G Bellinger, J Benjamin, D Bensinger, J Beretvas, A Berge, JP Berryhill, J Bertolucci, S Bettelli, S Bevensee, B Bhatti, A Biery, K Bigongiari, C Binkley, M Bisello, D Blair, RE Blocker, C Blusk, S Bodek, A Bokhari, W Bolla, G Bonushkin, Y Bortoletto, D Boudreau, J Breccia, L Bromberg, C Bruner, N Brunetti, R Buckley-Geer, E Budd, HS Burkett, K Busetto, G Byon-Wagner, A Byrum, KL Campbell, M Caner, A Carithers, W Carlsmith, D Cassada, J Castro, A Cauz, D Cerri, A Chang, PS Chang, PT Chao, HY Chapman, J Cheng, MT Chertok, M Chiarelli, G Chiou, CN Christofek, L Chu, ML Cihangir, S Clark, AG Cobal, M Cocca, E Contreras, M Conway, J Cooper, J Cordelli, M Costanzo, D Couyoumtzelis, C Cronin-Hennessy, D Culbertson, R Dagenhart, D Daniels, T DeJongh, F Dell'Agnello, S Dell'Orso, M Demina, R Demortier, L Deninno, M Derwent, PF Devlin, T Dittmann, JR Donati, S Done, J Dorigo, T Eddy, N Einsweiler, K Elias, JE Ely, R Engels, E Errede, D Errede, S Fan, Q Feild, RG Feng, Z Ferretti, C Fiori, I Flaugher, B Foster, GW Franklin, M Freeman, J Friedman, J Fukui, Y Galeotti, S Gallinaro, M Ganel, O Garcia-Sciveres, M Garfinkel, AF Gay, C Geer, S Gerdes, DW Giannetti, P Giokaris, N Giromini, P Giusti, G Gold, M Gordon, A Goshaw, AT Gotra, Y Goulianos, K Grassmann, H Groer, L Grosso-Pilcher, C Guillian, G da Costa, JG Guo, RS Haber, C Hafen, E Hahn, SR Hamilton, R Handa, T Handler, R Happacher, F Hara, K Hardman, AD Harris, RM Hartmann, F Hauser, J Hayashi, E Heinrich, J Hao, W Hinrichsen, B Hoffman, KD Hohlmann, M Holck, C HOllebeek, R Holloway, L Huang, Z Huffman, BT Hughes, R Huston, J Hurth, J Ikeda, H Incagli, M Incandela, J Introzzi, G Iwai, J Iwata, Y James, E Jensen, H Joshi, U Kajfasz, E Kambara, H Kamon, T Kaneko, T Karr, K Kasha, H Kato, Y Keaffaber, TA Kelley, K Kennedy, RD Kephart, R Kestenbaum, D Khazins, D Kikuchi, T Kim, BJ Kim, HS Kim, SH Kim, YK Kirsch, L Klimenko, S Knoblauch, D Koehn, P Kondo, K Kongeter, A Konigsberg, J Kordas, K Korytov, A Kovacs, E Kowald, W Kroll, J Kruse, M Kuhlmann, SE Kuns, E KUrino, K Kuwabara, T Laasanen, AT Lami, S Lammel, S Lamoureux, JI Lancaster, M Lanzoni, M Latino, G LeCompte, T Leone, S Lewis, JD Limon, P Lindgren, M Liss, TM Liu, JB Liu, YC Lockyer, N Long, O Loomis, C Loreti, M Lucchesi, D Lukens, P Lusin, S Lys, J Maeshima, K Maksimovic, P Mangano, M Mariotti, M Marriner, JP Martin, A Matthews, JAJ Mazzanti, P McIntyre, P Melese, P Menguzzato, M Menzione, A Meschi, E Metzler, S Miao, C Miao, T Michail, G Miller, R Minato, H Miscetti, S Mishina, M Miyashita, S Moggi, N Moore, E Morita, Y Mukherjee, A Muller, T Murat, P Murgia, S Nakada, H Nakano, I Nelson, C Neuberger, D Newman-Holmes, C Ngan, CYP Nodulman, L Oh, SH Ohmoto, T Ohsugi, T Oishi, R Okabe, M Okusawa, T Olsen, J Pagliarone, C Paoletti, R Papadimitriou, V Pappas, SP Parashar, N Parri, A Patrick, J Pauletta, G Paulini, M Perazzo, A Pescara, L Peters, MD Phillips, TJ Piacentino, G Pillai, M Pitts, KT Plunkett, R Pondrom, L Proudfoot, J Ptohos, F Punzi, G Ragan, K Reher, D Reischl, M Ribon, A Rimondi, F Ristori, L Robertson, WJ Rodrigo, T Rolli, S Rosenson, L Roser, R Saab, T Sakumoto, WK Saltzberg, D Sansoni, A Santi, L Sato, H Schlabach, P Schmidt, EE Schmidt, MP Scott, A Scribano, A Segler, S Seidel, S Seiya, Y Semeria, F Shah, T Shapiro, MD Shaw, NM Shepard, PF Shibayama, T Shimojima, M Shochet, M Siegrist, J Sill, A Sinervo, P Singh, P Sliwa, K Smith, C Snider, FD Spalding, J Speer, T Sphicas, P Spiegel, L Spinella, F Spiropulu, M Stanco, L Steele, J Stefanini, A Strohmer, R Strologas, J Strumia, F Stuart, D Sumorok, K Suzuki, J Suzuki, T Takahashi, T Takano, T Takashima, R Takikawa, K Tanaka, M Tannenbaum, B Tartarelli, F Taylor, W Tecchio, M Teng, PK Teramoto, Y Terashi, K Tether, S Theriot, D Thomas, TL Thurman-Keup, R Timko, M Tipton, P Titov, A Tkaczyk, S Toback, D Tollefson, K Tollestrup, A Toyoda, H Trischuk, W de Troconiz, JF Truitt, S Tseng, J Turini, N Uchida, T Ukegawa, F van den Brink, SC Vejcik, S Velev, G Vidal, R Vilar, R Vucinic, D Wagner, RG Wagner, RL Wahl, J Wallace, NB Walsh, AM Wang, C Wang, CH Wang, MJ Warburton, A Watanabe, T Watts, T Webb, R Wei, C Wenzel, H Wester, WC Wicklund, AB Wicklund, E Wilkinson, R Williams, HH Wilson, P Winer, BL Winn, D Wolinski, D Wolinski, J Worm, S Wu, X Wyss, J Yagil, A Yao, W Yasuoka, K Yeh, GP Yeh, P Yoh, J Yosef, C Yoshida, T Yu, I Zanetti, A Zetti, F Zucchelli, S TI Measurement of the B-0-(B)over-bar(0) oscillation frequency using pi-B meson charge-flavor correlations in p(p)over-bar collisions at root s=1.8 TeV SO PHYSICAL REVIEW LETTERS LA English DT Article ID = 1.8 TEV; SEMILEPTONIC DECAYS; QUARK PRODUCTION AB We present a measurement of the B-0 <-> (B) over bar(0) oscillation frequency a flavor tagging method based on correlations of B meson flavor with the charge of other particles produced in collisions at root s = 1.8 TeV. Such correlations are expected to arise from b quark hadronization and from B** decays. We partially reconstruct B mesons using the semileptonic decays B-0 --> l(+) D-(*-)X and B+ --> l(+)(D) over bar(0)X. From the oscillation frequency, we obtain the mass difference between the two B-0 mass eigenstates, Delta m(d) = 0.471(+0.068)(+0.078)(stat) +/- 0.034(syst)(h) over bar ps(-1), and measure the efficiency and purity of this flavor tagging method for both charged and neutral B mesons. C1 Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. Argonne Natl Lab, Argonne, IL 60439 USA. Univ Bologna, Ist Nazl Fis Nucl, I-40127 Bologna, Italy. Brandeis Univ, Waltham, MA 02254 USA. Univ Calif Los Angeles, Los Angeles, CA 90024 USA. Univ Chicago, Chicago, IL 60637 USA. Duke Univ, Durham, NC 27708 USA. Fermilab Natl Accelerator Lab, Batavia, IL 60510 USA. Univ Florida, Gainesville, FL 32611 USA. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Geneva, CH-1211 Geneva 4, Switzerland. Harvard Univ, Cambridge, MA 02138 USA. Hiroshima Univ, Higashihiroshima 724, Japan. Univ Illinois, Urbana, IL 61801 USA. McGill Univ, Inst Particle Phys, Montreal, PQ H3A 2T8, Canada. Univ Toronto, Toronto, ON M5S 1A7, Canada. Johns Hopkins Univ, Baltimore, MD 21218 USA. Univ Karlsruhe, Inst Expt Kernphys, D-76128 Karlsruhe, Germany. Kek Nat Lab High Energy Phys, Ibaraki, Osaka 305, Japan. Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. MIT, Cambridge, MA 02139 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Univ New Mexico, Albuquerque, NM 87131 USA. Ohio State Univ, Columbus, OH 43210 USA. Osaka City Univ, Osaka 588, Japan. Univ Padua, Inst Nazl Fis Nucl, I-36132 Padua, Italy. Univ Penn, Philadelphia, PA 19104 USA. Univ Pisa, Ist Nazl Fis Nucl, I-56100 Pisa, Italy. Scuola Normale Super Pisa, I-56100 Pisa, Italy. Univ Pittsburgh, Pittsburgh, PA 15260 USA. Purdue Univ, W Lafayette, IN 47907 USA. Univ Rochester, Rochester, NY 14627 USA. Rockefeller Univ, New York, NY 10021 USA. Rutgers State Univ, Piscataway, NJ 08855 USA. Acad Sinica, Taipei 11530, Taiwan. Texas A&M Univ, College Stn, TX 77843 USA. Texas Tech Univ, Lubbock, TX 79409 USA. Univ Trieste, Ist Nazl Fis Nucl, Udine, Italy. Univ Tsukuba, Tsukuba, Ibaraki 315, Japan. Tufts Univ, Medford, MA 02155 USA. Waseda Univ, Tokyo 169, Japan. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06520 USA. RP Natl Lab High Energy Phys, KEK, Tsukuba, Ibaraki 305, Japan. RI Lancaster, Mark/C-1693-2008; Vucinic, Dejan/C-2406-2008; Azzi, Patrizia/H-5404-2012; Punzi, Giovanni/J-4947-2012; Chiarelli, Giorgio/E-8953-2012; Warburton, Andreas/N-8028-2013; Paulini, Manfred/N-7794-2014; Introzzi, Gianluca/K-2497-2015 OI Azzi, Patrizia/0000-0002-3129-828X; Punzi, Giovanni/0000-0002-8346-9052; Chiarelli, Giorgio/0000-0001-9851-4816; Warburton, Andreas/0000-0002-2298-7315; Paulini, Manfred/0000-0002-6714-5787; Introzzi, Gianluca/0000-0002-1314-2580 NR 21 TC 44 Z9 44 U1 0 U2 0 PU AMER PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 EI 1079-7114 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2057 EP 2062 DI 10.1103/PhysRevLett.80.2057 PG 6 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400009 ER PT J AU Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amidi, E Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Borders, J Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, M Fatyga, MK Featherly, J Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, J Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, G Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lan, H Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D LInn, SL Linnemann, J Lipton, R Liu, Q Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Mao, HS Markeloff, R Markosky, L Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibbon, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A de Miranda, JM Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Nicola, M Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, YM Partridge, R Parua, N Paterno, M Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, A Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yanagisawa, C Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A AF Abbott, B Abolins, M Acharya, BS Adam, I Adams, DL Adams, M Ahn, S Aihara, H Alves, GA Amidi, E Amos, N Anderson, EW Astur, R Baarmand, MM Baden, A Balamurali, V Balderston, J Baldin, B Banerjee, S Bantly, J Barberis, E Bartlett, JF Bazizi, K Belyaev, A Beri, SB Bertram, I Bezzubov, VA Bhat, PC Bhatnagar, V Bhattacharjee, M Biswas, N Blazey, G Blessing, S Bloom, P Boehnlein, A Bojko, NI Borcherding, F Borders, J Boswell, C Brandt, A Brock, R Bross, A Buchholz, D Burtovoi, VS Butler, JM Carvalho, W Casey, D Casilum, Z Castilla-Valdez, H Chakraborty, D Chang, SM Chekulaev, SV Chen, LP Chen, W Choi, S Chopra, S Choudhary, BC Christenson, JH Chung, M Claes, D Clark, AR Cobau, WG Cochran, J Cooper, WE Cretsinger, C Cullen-Vidal, D Cummings, MAC Cutts, D Dahl, OI Davis, K De, K Del Signore, K Demarteau, M Denisov, D Denisov, SP Diehl, HT Diesburg, M Di Loreto, G Draper, P Ducros, Y Dudko, LV Dugad, SR Edmunds, D Ellison, J Elvira, VD Engelmann, R Eno, S Eppley, G Ermolov, P Eroshin, OV Evdokimov, VN Fahland, T Fatyga, M Fatyga, MK Featherly, J Feher, S Fein, D Ferbel, T Finocchiaro, G Fisk, HE Fisyak, Y Flattum, E Forden, GE Fortner, M Frame, KC Fuess, S Gallas, E Galyaev, AN Gartung, P Geld, TL Genik, RJ Genser, K Gerber, CE Gibbard, B Glenn, S Gobbi, B Goforth, M Goldschmidt, A Gomez, B Gomez, G Goncharov, PI Solis, JLG Gordon, H Goss, LT Gounder, K Goussiou, A Graf, N Grannis, PD Green, DR Green, J Greenlee, H Grim, G Grinstein, S Grossman, N Grudberg, P Grunendahl, S Guglielmo, G Guida, JA Guida, JM Gupta, A Gurzhiev, SN Gutierrez, P Gutnikov, YE Hadley, NJ Haggerty, H Hagopian, S Hagopian, V Hahn, KS Hall, RE Hansen, S Hauptman, JM Hedin, D Heinson, AP Heintz, U Hernandez-Montoya, R Heuring, T Hirosky, R Hobbs, JD Hoeneisen, B Hoftun, JS Hsieh, F Hu, T Hu, T Huehn, T Ito, AS James, E Jaques, J Jerger, SA Jesik, R Jiang, JZY Joffe-Minor, T Johns, K Johnson, M Jonckheere, A Jones, M Jostlein, H Jun, SY Jung, CK Kahn, S Kalbfleisch, G Kang, JS Kehoe, R Kelly, ML Kim, CL Kim, SK Klatchko, A Klima, B Klopfenstein, G Klyukhin, VI Kochetkov, VI Kohli, JM Koltick, D Kostritskiy, AV Kotcher, J Kotwal, AV Kourlas, J Kozelov, AV Kozlovski, EA Krane, J Krishnaswamy, MR Krzywdzinski, S Kunori, S Lami, S Lan, H Lander, R Landry, F Landsberg, G Lauer, B Leflat, A Li, H Li, J Li-Demarteau, QZ Lima, JGR Lincoln, D LInn, SL Linnemann, J Lipton, R Liu, Q Liu, YC Lobkowicz, F Loken, SC Lokos, S Lueking, L Lyon, AL Maciel, AKA Madaras, RJ Madden, R Magana-Mendoza, L Mani, S Mao, HS Markeloff, R Markosky, L Marshall, T Martin, MI Mauritz, KM May, B Mayorov, AA McCarthy, R McDonald, J McKibbon, T McKinley, J McMahon, T Melanson, HL Merkin, M Merritt, KW Miettinen, H Mincer, A de Miranda, JM Mishra, CS Mokhov, N Mondal, NK Montgomery, HE Mooney, P da Motta, H Murphy, C Nang, F Narain, M Narasimham, VS Narayanan, A Neal, HA Negret, JP Nemethy, P Nicola, M Norman, D Oesch, L Oguri, V Oltman, E Oshima, N Owen, D Padley, P Pang, M Para, A Park, YM Partridge, R Parua, N Paterno, M Perkins, J Peters, M Piegaia, R Piekarz, H Pischalnikov, Y Podstavkov, VM Pope, BG Prosper, HB Protopopescu, S Qian, J Quintas, PZ Raja, R Rajagopalan, S Ramirez, O Rasmussen, L Reucroft, S Rijssenbeek, M Rockwell, T Roe, NA Rubinov, P Ruchti, R Rutherfoord, J Sanchez-Hernandez, A Santoro, A Sawyer, L Schamberger, RD Schellman, H Sculli, J Shabalina, E Shaffer, C Shankar, HC Shivpuri, RK Shupe, M Singh, H Singh, JB Sirotenko, V Smart, W Smith, A Smith, RP Snihur, R Snow, GR Snow, J Snyder, S Solomon, J Sood, PM Sosebee, M Sotnikova, N Souza, M Spadafora, AL Stephens, RW Stevenson, ML Stewart, D Stoianova, DA Stoker, D Strauss, M Streets, K Strovink, M Sznajder, A Tamburello, P Tarazi, J Tartaglia, M Thomas, TLT Thompson, J Trippe, TG Tuts, PM Varelas, N Varnes, EW Vititoe, D Volkov, AA Vorobiev, AP Wahl, HD Wang, G Warchol, J Watts, G Wayne, M Weerts, H White, A White, JT Wightman, JA Willis, S Wimpenny, SJ Wirjawan, JVD Womersley, J Won, E Wood, DR Xu, H Yamada, R Yamin, P Yanagisawa, C Yang, J Yasuda, T Yepes, P Yoshikawa, C Youssef, S Yu, J Yu, Y Zhu, ZH Zieminska, D Zieminski, A Zverev, EG Zylberstejn, A TI Measurement of the top quark mass using dilepton events SO PHYSICAL REVIEW LETTERS LA English DT Article ID LIKELIHOOD METHOD; MISSING MOMENTUM; RECONSTRUCTION; DETECTOR; DECAY AB The D0 Collaboration has performed a measurement of the top quark mass m(t) based on six candidate events for the process --> bW(+)(b) over bar W-, where the W bosons decay to e nu or mu nu. This sample was collected during an exposure of the D0 detector to an integrated luminosity of 125 pb(-1) of root s = 1.8 TeV collisions. We obtain m(t) = 168.4 +/- 12.3(stat) +/- 3.6(syst) GeV/c(2), consistent with the measurement obtained using single-lepton events. Combination of the single-lepton and dilepton results yields m(t) = 172.0 +/- 7.5 GeV/c(2). C1 Univ Los Andes, Bogota, Colombia. NYU, New York, NY 10003 USA. Univ Arizona, Tucson, AZ 85721 USA. Boston Univ, Boston, MA 02215 USA. Brookhaven Natl Lab, Upton, NY 11973 USA. Brown Univ, Providence, RI 02912 USA. Univ Buenos Aires, Buenos Aires, DF, Argentina. Univ Calif Davis, Davis, CA 95616 USA. Univ Calif Irvine, Irvine, CA 92697 USA. Univ Calif Riverside, Riverside, CA 92521 USA. Ctr Brasileiro Pesquisas Fis, LAFEX, Rio De Janeiro, Brazil. CINVESTAV, Mexico City 14000, DF, Mexico. Columbia Univ, New York, NY 10027 USA. Univ Delhi, Delhi 110007, India. Fermi Natl Accelerator Lab, Batavia, IL 60510 USA. Florida State Univ, Tallahassee, FL 32306 USA. Univ Hawaii, Honolulu, HI 96822 USA. Univ Illinois, Chicago, IL 60607 USA. Indiana Univ, Bloomington, IN 47405 USA. Iowa State Univ Sci & Technol, Ames, IA 50011 USA. Korea Univ, Seoul 136701, South Korea. Kyungsung Univ, Pusan 608736, South Korea. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Berkeley, CA 94720 USA. Univ Maryland, College Pk, MD 20742 USA. Univ Michigan, Ann Arbor, MI 48109 USA. Michigan State Univ, E Lansing, MI 48824 USA. Moscow State Univ, Moscow, Russia. Univ Nebraska, Lincoln, NE 68588 USA. Northeastern Univ, Boston, MA 02115 USA. No Illinois Univ, De Kalb, IL 60115 USA. Northwestern Univ, Evanston, IL 60208 USA. Univ Notre Dame, Notre Dame, IN 46556 USA. Univ Oklahoma, Norman, OK 73019 USA. Punjab Univ, Chandigarh 160014, India. Protvino High Energy Phys Inst, Protvino 142284, Russia. Purdue Univ, W Lafayette, IN 47907 USA. Rice Univ, Houston, TX 77005 USA. Univ Estadual Rio de Janiero, Rio De Janeiro, Brazil. Univ Rochester, Rochester, NY 14627 USA. CEA, DAPNIA, Serv Phys Particules, CE Saclay, Gif Sur Yvette, France. Seoul Natl Univ, Seoul, South Korea. SUNY Stony Brook, Stony Brook, NY 11794 USA. Tata Inst Fundamental Res, Mumbai 400005, India. Univ Texas, Arlington, TX 76019 USA. Texas A&M Univ, College Stn, TX 77843 USA. RP Abbott, B (reprint author), NYU, New York, NY 10003 USA. RI Kim, Sun Kee/G-2042-2015; Chekulaev, Sergey/O-1145-2015; Sznajder, Andre/L-1621-2016; Aihara, Hiroaki/F-3854-2010; Shivpuri, R K/A-5848-2010; Gutierrez, Phillip/C-1161-2011; Roe, Natalie/A-8798-2012; Dudko, Lev/D-7127-2012; Leflat, Alexander/D-7284-2012; Merkin, Mikhail/D-6809-2012; Klyukhin, Vyacheslav/D-6850-2012; De, Kaushik/N-1953-2013; Oguri, Vitor/B-5403-2013; Alves, Gilvan/C-4007-2013; Belyaev, Alexander/F-6637-2015 OI Kim, Sun Kee/0000-0002-0013-0775; Sznajder, Andre/0000-0001-6998-1108; Baarmand, Marc/0000-0002-9792-8619; Aihara, Hiroaki/0000-0002-1907-5964; Dudko, Lev/0000-0002-4462-3192; Klyukhin, Vyacheslav/0000-0002-8577-6531; De, Kaushik/0000-0002-5647-4489; Belyaev, Alexander/0000-0002-1733-4408 NR 16 TC 87 Z9 87 U1 0 U2 3 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2063 EP 2068 DI 10.1103/PhysRevLett.80.2063 PG 6 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400010 ER PT J AU Wuosmaa, AH Ahmad, I Fischer, SM Greene, JP Hackman, G Nanal, V Savard, G Schiffer, JP Wilt, P Austin, SH Brown, BA Freedman, SJ Connell, JJ AF Wuosmaa, AH Ahmad, I Fischer, SM Greene, JP Hackman, G Nanal, V Savard, G Schiffer, JP Wilt, P Austin, SH Brown, BA Freedman, SJ Connell, JJ TI beta(+) decay partial half-life of Mn-54 and cosmic ray chronometry SO PHYSICAL REVIEW LETTERS LA English DT Article ID SPECTROMETER AB The weak beta(+) decay of the astrophysically significant radioisotope Mn-54 has been observed. The energies of positrons from a chemically purified Mn-54 source were measured using the APEX spectrometer at Argonne National Laboratory. We deduce a beta(+) decay branch of (1.20 +/- 0.26) X 10(-9), corresponding to a partial half-life of (7.1 +/- 1.5) x 10(8) yr. The implications of this value for cosmic-ray confinement times are discussed in light of recent satellite measurements of the cosmic-ray abundance of Mn-54. C1 Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. Michigan State Univ, Natl Superconducting Cyclotron Lab, E Lansing, MI 48824 USA. Michigan State Univ, Dept Phys & Astron, E Lansing, MI 48824 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Chicago, Enrico Fermi Inst, Chicago, IL 60637 USA. RP Wuosmaa, AH (reprint author), Argonne Natl Lab, Div Phys, Argonne, IL 60439 USA. NR 20 TC 15 Z9 15 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2085 EP 2088 DI 10.1103/PhysRevLett.80.2085 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400015 ER PT J AU Ha, T Glass, J Enderle, T Chemla, DS Weiss, S AF Ha, T Glass, J Enderle, T Chemla, DS Weiss, S TI Hindered rotational diffusion and rotational jumps of single molecules SO PHYSICAL REVIEW LETTERS LA English DT Article ID OPTICAL MICROSCOPY; SPECTROSCOPY; EXCITATION; DYNAMICS AB We extended the sensitivity of fluorescence polarization anisotropy measurements to the single molecule level by studying the polarization response of single fluorophores rapidly rotating in liquid. Comparison with a simple model calculation allows us to obtain information on the hindered motion as well as on the rotational diffusion in the presence of specific molecular interactions. We also observed rotational jumps between surface-bound and unbound states and show that they are, similar to jumps to long dark states, photoactivated. C1 Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RP Ha, T (reprint author), Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, 1 Cyclotron Rd, Berkeley, CA 94720 USA. RI Ha, Taekjip/B-9506-2009; weiss, shimon/B-4164-2009 OI Ha, Taekjip/0000-0003-2195-6258; weiss, shimon/0000-0002-0720-5426 NR 26 TC 139 Z9 140 U1 1 U2 18 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2093 EP 2096 DI 10.1103/PhysRevLett.80.2093 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400017 ER PT J AU Mineev-Weinstein, M AF Mineev-Weinstein, M TI Selection of the Saffman-Taylor finger width in the absence of surface tension: An exact result SO PHYSICAL REVIEW LETTERS LA English DT Article ID INTERFACE DYNAMICS; PATTERN-FORMATION; ANALYTIC THEORY; GROWTH AB Using exact time-dependent nonsingular solutions [Mineev-Weinstein and Dawson, Phys. Rev. E 50, R24 (1994); Dawson and Mineev-Weinstein, Physica (Amsterdam) 73D, 373 (1994)], we solve the Saffman-Taylor finger selection problem in the absence of surface tension. We show that a generic interface in a Hele-Shaw cell evolves to a nonlinearly stable single uniformly advancing finger occupying one-half of the channel width. This result contradicts the generally accepted belief that surface tension is indispensable for the selection of the 1/2-width finger. C1 Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Mineev-Weinstein, M (reprint author), Univ Calif Los Alamos Natl Lab, Div Theoret, MS-B213, Los Alamos, NM 87545 USA. NR 20 TC 48 Z9 48 U1 0 U2 6 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2113 EP 2116 DI 10.1103/PhysRevLett.80.2113 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400022 ER PT J AU Schmid, AK Hwang, RQ Bartelt, NC AF Schmid, AK Hwang, RQ Bartelt, NC TI Predicting the future of a complicated surface structure: Grain coarsening of p(2x2)O/Ru(0001) SO PHYSICAL REVIEW LETTERS LA English DT Article ID KINETICS; GROWTH AB We have used scanning tunneling microscopy to study grain boundary motion in oxygen films adsorbed on Ru(0001). Starting from an analysis of atomically resolved images of the thermal motion of oxygen atoms within the grain boundaries, we are able to successfully predict the future of complicated configurations of grains involving several hundred thousand atoms over several hours. The detail to which theory can reproduce experimental histories shows the precision to which previously hypothetical models of surface kinetics can now be verified. C1 Sandia Natl Labs, Livermore, CA 94551 USA. RP Schmid, AK (reprint author), Sandia Natl Labs, Livermore, CA 94551 USA. NR 8 TC 9 Z9 9 U1 0 U2 1 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2153 EP 2156 DI 10.1103/PhysRevLett.80.2153 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400032 ER PT J AU de Vries, SA Goedtkindt, P Bennett, SL Huisman, WJ Zwanenburg, MJ Smilgies, DM De Yoreo, JJ van Enckevort, WJP Bennema, P Vlieg, E AF de Vries, SA Goedtkindt, P Bennett, SL Huisman, WJ Zwanenburg, MJ Smilgies, DM De Yoreo, JJ van Enckevort, WJP Bennema, P Vlieg, E TI Surface atomic structure of KDP crystals in aqueous solution: An explanation of the growth shape SO PHYSICAL REVIEW LETTERS LA English DT Article ID DIHYDROGEN PHOSPHATE CRYSTALS; X-RAY REFLECTIVITY; LAYER GROWTH; MECHANISM; WATER; DIFFRACTION; MORPHOLOGY; INTERFACE; CALCITE; KH2PO4 AB With this study on KDP, we present an interface atomic structure determination of a crystal in contact with its growth solution. Using x-ray diffraction at a third-generation synchrotron radiation source, the structure of both the {101} and {100} faces has been determined. We found that the {101} faces are terminated by a layer of K+ ions and not by H2PO4- groups, resolving a long-standing issue that could not be predicted by theory. This result leads to an atomic-scale explanation of the influence of metal impurities on the macroscopic growth morphology. C1 FOM, Inst Atom & Mol Phys, NL-1098 SJ Amsterdam, Netherlands. Univ Instelling Antwerp, Dept Chem, B-2610 Wilrijk, Belgium. SERC, Daresbury Lab, CCLRC, Warrington WA4 4AD, Cheshire, England. European Synchrotron Radiat Facil, F-38043 Grenoble, France. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94550 USA. Catholic Univ Nijmegen, Dept Solid State Chem, RIM, NL-6525 ED Nijmegen, Netherlands. RP de Vries, SA (reprint author), FOM, Inst Atom & Mol Phys, Kruislaan 407, NL-1098 SJ Amsterdam, Netherlands. RI van Enckevort, Willem/D-5226-2012; Vlieg, Elias/G-3386-2012; Goedtkindt, Peter/K-4458-2012; OI Goedtkindt, Peter/0000-0001-8572-6000; Smilgies, Detlef/0000-0001-9351-581X NR 24 TC 105 Z9 105 U1 5 U2 23 PU AMERICAN PHYSICAL SOC PI COLLEGE PK PA ONE PHYSICS ELLIPSE, COLLEGE PK, MD 20740-3844 USA SN 0031-9007 J9 PHYS REV LETT JI Phys. Rev. Lett. PD MAR 9 PY 1998 VL 80 IS 10 BP 2229 EP 2232 DI 10.1103/PhysRevLett.80.2229 PG 4 WC Physics, Multidisciplinary SC Physics GA ZA636 UT WOS:000072385400051 ER PT J AU Mair, RA Prepost, R Garwin, EL Maruyama, T AF Mair, RA Prepost, R Garwin, EL Maruyama, T TI Measurement of the deformation potentials for GaAs using polarized photoluminescence SO PHYSICS LETTERS A LA English DT Article ID SURFACE-MORPHOLOGY; STRAIN; SEMICONDUCTORS; DISLOCATIONS AB The deformation potentials a, b and d for GaAs have been determined from polarized photoluminescence measurements upon a set of epitaxially grown strained GaAs structures possessing varying levels of compressive biaxial lattice strain. X-ray diffraction measurements yield values for the degree of lattice strain while the polarized photoluminescence measurements permit a separate determination to be made of the heavy hole and light hole band energies. Correlation of these data allows for the determination of the deformation potentials within the context of the orbital-strain Hamiltonian. (C) 1998 Published by Elsevier Science B.V. C1 Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Mair, RA (reprint author), Univ Wisconsin, Dept Phys, 1150 Univ Ave, Madison, WI 53706 USA. NR 26 TC 2 Z9 2 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0375-9601 J9 PHYS LETT A JI Phys. Lett. A PD MAR 9 PY 1998 VL 239 IS 4-5 BP 277 EP 284 DI 10.1016/S0375-9601(98)00036-X PG 8 WC Physics, Multidisciplinary SC Physics GA ZE089 UT WOS:000072756600015 ER PT J AU Wallen, SL Palmer, BJ Fulton, JL AF Wallen, SL Palmer, BJ Fulton, JL TI The ion pairing and hydration structure of Ni2+ in supercritical water at 425 degrees C determined by x-ray absorption fine structure and molecular dynamics studies SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID HYDROTHERMAL SOLUTIONS; NEUTRON-DIFFRACTION; MULTIPLE-SCATTERING; AQUEOUS-SOLUTIONS; NICKEL; ASSOCIATION; SIMULATION; CHLORIDE; SPECTRA; SOLUBILITY AB The ion pairing structure of Ni(Br)(2) solutions (0.2 and 0.4 molal) under supercritical conditions was determined using x-ray absorption fine structure (X4FS) spectroscopy. These first measurements of the average bulk structure show that approximately one Br-counterion is associated with each Ni2+. The Ni2+-to-Br- distance of 2.40 Angstrom is very accurately determined and the strength of this interaction, as indicated by the Debye-Waller factor (sigma(2) = 0.009 Angstrom(2)), shows that the bromine anion is very tightly bound to the nickel cation under these supercritical conditions. In addition to the onset of ion pairing interactions, there is also a dramatic transition in the hydration structure. Results show a loss of about 50% of the waters in the first shell upon going from ambient to a hydrothermal condition of 425 degrees C and 690 bar. Finally, we use molecular dynamics simulations with refined intermolecular potentials to directly calculate XAFS spectra that are shown to quantitatively reproduce the experimental results for the ion pair and hydration structure. (C) 1998 American Institute of Physics. [S0021-9606(98)52410-5]. C1 Pacific NW Natl Lab, Environm & Hlth Sci Div, Richland, WA 99352 USA. RP Pacific NW Natl Lab, Environm & Hlth Sci Div, Richland, WA 99352 USA. NR 50 TC 76 Z9 78 U1 3 U2 11 PU AMER INST PHYSICS PI MELVILLE PA 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA SN 0021-9606 EI 1089-7690 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 8 PY 1998 VL 108 IS 10 BP 4039 EP 4046 DI 10.1063/1.475838 PG 8 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZA530 UT WOS:000072373500023 ER PT J AU Choi, H Mordaunt, DH Bise, RT Taylor, TR Neumark, DM AF Choi, H Mordaunt, DH Bise, RT Taylor, TR Neumark, DM TI Photodissociation of triplet and singlet states of the CCO radical SO JOURNAL OF CHEMICAL PHYSICS LA English DT Article ID DIODE-LASER SPECTROSCOPY; CARBON SUBOXIDE; PHOTOELECTRON-SPECTROSCOPY; FAST BEAM; DYNAMICS; C2O; PHOTOLYSIS; NM; MOLECULES; CONSTANTS AB The tripler and singlet states of the ketenylidene (CCO) radical are investigated using fast radical beam photofragment translational spectroscopy, in which CCO is generated by laser photodetachment of CCO- and subsequently photodissociated, and anion photoelectron spectroscopy. In the photodissociation experiment, two bands in which the upper state of CCO predissociates are studied, Photodissociation from excitation of the (A) over tilde (II)-I-3-(X) over tilde(3) Sigma(-) band in CCO is observed from 16 666-23 529 cm(-1); resonances are observed and assigned to excited vibrational levels involving all three vibrational modes. We also report the first observation of the (c) over tilde(1)II-(a) over tilde(1) Delta band in CCO. Here, the (a) over tilde Delta state of CCO is generated by laser photodetachment at higher photon energy than was used to generate the (X) over tilde(3) Sigma state, The (c) over tilde(1)II state is approximately located by photoelectron spectroscopy of CCO-, and the photodissociation experiment shows that the origin of the (c) over tilde(1)II-(a) over tilde(1) Delta band occurs around 17 170 cm(-1). Kinetic-energy release spectra from both bands yield accurate values for the C-CO bond dissociation energy and heat of formation of CCO: D-0(C-CO)=2.24+/-0.02 eV (51.7+/-0.5 kcal/mol) and Delta H-f,298(0)(CCO)=4.04+/-0.02 eV (91.1 +/-0.5 kcal/mol). Although the translational-energy distributions resulting from excitation to the (A) over tilde(3)II and (c) over tilde(1)II states are clearly nonstatistical, consideration of the potential-energy surfaces indicates that dissociation from both states occurs via radiationless transitions to the (X) over tilde(3) Sigma(-) state. (C) 1998 American Institute of Physics. C1 Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Chem Sci, Berkeley, CA 94720 USA. RP Choi, H (reprint author), Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA. RI Neumark, Daniel/B-9551-2009 OI Neumark, Daniel/0000-0002-3762-9473 NR 48 TC 38 Z9 38 U1 1 U2 9 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 8 PY 1998 VL 108 IS 10 BP 4070 EP 4078 DI 10.1063/1.475839 PG 9 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZA530 UT WOS:000072373500027 ER PT J AU Evans, DJ Searles, DJ Hoover, WG Hoover, CG Holian, BL Posch, HA Morriss, GP AF Evans, DJ Searles, DJ Hoover, WG Hoover, CG Holian, BL Posch, HA Morriss, GP TI Comment on "Modified nonequilibrium molecular dynamics for fluid flows with energy conservation" [J. Chem. Phys. 106, 5615 (1997)] SO JOURNAL OF CHEMICAL PHYSICS LA English DT Letter ID LYAPUNOV EXPONENTS; RESPONSE THEORY; STEADY-STATES; 2ND LAW C1 Australian Natl Univ, Res Sch Chem, Canberra, ACT 2601, Australia. Univ Calif Lawrence Livermore Natl Lab, Livermore, CA 94551 USA. UC Davis Livermore, Livermore, CA 94551 USA. Univ Calif Los Alamos Natl Lab, Los Alamos, NM 87545 USA. Univ Vienna, A-1090 Vienna, Austria. Univ New S Wales, Sydney, NSW 2052, Australia. RP Evans, DJ (reprint author), Australian Natl Univ, Res Sch Chem, GPO Box 4, Canberra, ACT 2601, Australia. RI Bernhardt, Debra/A-8174-2008; Evans, Denis/C-1653-2009 OI Bernhardt, Debra/0000-0003-1346-8318; NR 21 TC 18 Z9 18 U1 0 U2 1 PU AMER INST PHYSICS PI WOODBURY PA CIRCULATION FULFILLMENT DIV, 500 SUNNYSIDE BLVD, WOODBURY, NY 11797-2999 USA SN 0021-9606 J9 J CHEM PHYS JI J. Chem. Phys. PD MAR 8 PY 1998 VL 108 IS 10 BP 4351 EP 4352 DI 10.1063/1.475843 PG 2 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZA530 UT WOS:000072373500060 ER PT J AU Anders, A Brown, IG MacGill, RA Dickinson, MR AF Anders, A Brown, IG MacGill, RA Dickinson, MR TI 'Triggerless' triggering of vacuum arcs SO JOURNAL OF PHYSICS D-APPLIED PHYSICS LA English DT Article ID ION SOURCES; DEPOSITION AB Vacuum arcs can be initiated without external means of power enhancement at the cathode surface (by using a high-voltage trigger, laser triggering, and so on). Are initiation by simply applying the relatively low voltage of the are power supply is possible if the cathode-anode-separating insulator is coated with a conducting layer and the current at the layer-cathode interface is concentrated at one or a few contact points. The local power density at these contact points can exceed 10(16) W m(-3) which is sufficient for plasma production and thus are initiation. This 'triggerless' principle has been tested successfully with a large number of cathode materials. One extended test was performed with titanium and more than 10(6) pulsed vacuum are initiations have been obtained. C1 Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RP Anders, A (reprint author), Univ Calif Berkeley, Ernest Orlando Lawrence Berkeley Natl Lab, Berkeley, CA 94720 USA. RI Anders, Andre/B-8580-2009 OI Anders, Andre/0000-0002-5313-6505 NR 24 TC 65 Z9 67 U1 0 U2 7 PU IOP PUBLISHING LTD PI BRISTOL PA DIRAC HOUSE, TEMPLE BACK, BRISTOL BS1 6BE, ENGLAND SN 0022-3727 J9 J PHYS D APPL PHYS JI J. Phys. D-Appl. Phys. PD MAR 7 PY 1998 VL 31 IS 5 BP 584 EP 587 DI 10.1088/0022-3727/31/5/015 PG 4 WC Physics, Applied SC Physics GA ZB514 UT WOS:000072480200015 ER PT J AU Grossman, JC Cote, M Louie, SG Cohen, ML AF Grossman, JC Cote, M Louie, SG Cohen, ML TI Electronic and structural properties of molecular C-36 SO CHEMICAL PHYSICS LETTERS LA English DT Article ID CARBON; ATOMS; FULLERENES; BORON; C-60; C28 AB Electronic and structural properties of several isomers of molecular C-36 are investigated using the pseudopotential density functional approach. These calculations show that substitutional doping with nitrogen can lead tu a 10% decrease in the C-C bond lengths of C-36, and this effect is explained using a simple example. Further. we have calculated endohedral binding energies and demonstrate that C-36 is perhaps the smallest fullerene size which can easily trap a range of atoms. The NMR chemical shifts, evaluated for the two lowest energy fullerene isomers, show that they are sufficiently different chemically to be distinguishable experimentally. (C) 1998 Elsevier Science B.V. C1 Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. Univ Calif Berkeley, Lawrence Berkeley Lab, Div Mat Sci, Berkeley, CA 94720 USA. RP Univ Calif Berkeley, Dept Phys, Berkeley, CA 94720 USA. RI Cote, Michel/H-3942-2012 OI Cote, Michel/0000-0001-9046-9491 NR 29 TC 110 Z9 113 U1 0 U2 3 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0009-2614 EI 1873-4448 J9 CHEM PHYS LETT JI Chem. Phys. Lett. PD MAR 6 PY 1998 VL 284 IS 5-6 BP 344 EP 349 DI 10.1016/S0009-2614(97)01433-4 PG 6 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZF810 UT WOS:000072935500008 ER PT J AU Zeng, LM Franzen, HF AF Zeng, LM Franzen, HF TI Synthesis and crystal structure of NdFe0.45Ge2 and HoFe0.33Ge2 SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE crystal structure; rare earth; helium; neodymium AB The compounds NdFe0.45Ge2 and HoFe0.33Ge2 have been synthesized and studied by single-crystal X-ray diffraction. They crystallize in the space group D-2h(17)-Cmcm of the orthorhombic system with Z=4 in the unit cell: a=4.091 (2) Angstrom, b=15.679(7) Angstrom, c=3.985(2) Angstrom, V=255.6(4) Angstrom(3) (T=296 K) for HoFe0.33Ge2; and a=4.214(2) Angstrom, b=16.455(9) Angstrom, c=4.070(2) Angstrom, V=282.2(4) Angstrom(3) (T=296 K) for NdFe0.45Ge2. The compounds exhibit the defect CeNiSi2 structure-type. (C) 1998 Elsevier Science S.A. C1 Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. RP Franzen, HF (reprint author), Iowa State Univ, Ames Lab, US DOE, Ames, IA 50011 USA. NR 8 TC 7 Z9 7 U1 1 U2 1 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 6 PY 1998 VL 267 IS 1-2 BP 86 EP 89 DI 10.1016/S0925-8388(97)00518-5 PG 4 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA ZE552 UT WOS:000072805000024 ER PT J AU Beeri, O Cohen, D Gavra, Z Johnson, JR Mintz, MH AF Beeri, O Cohen, D Gavra, Z Johnson, JR Mintz, MH TI High-pressure studies of the TiCr1.8-H-2 system Statistical thermodynamics above the critical temperature SO JOURNAL OF ALLOYS AND COMPOUNDS LA English DT Article DE high-pressure; hydrides; TiCr1.8; thermodynamics; statistical-thermodynamics ID HYDROGEN; ALLOYS AB Pressure-composition isotherms of the TiCr1.8-H-2 system were measured within the temperature range 298-433 degrees K and over a wide pressure range up to 1000 atm H-2. The above temperature range is well above the critical temperature, T-C, of the system. Hence, partial molal enthalpies and entropies of formation were evaluated as a function of hydrogen composition. Both thermodynamic quantities obeyed a linear decrease (i.e. becoming more negative) with increasing H/M atomic composition ratio (with M=Ti+Cr atomic content). The experimental isotherms were compared to calculated expressions derived by a rigid-metal sublattice statistical thermodynamics model. Two approximations applied in solving the model, the Bragg-Williams (B.W.) and the Quasi-Chemical (Q.C.) were compared, respectively. The pairwise nearest neighbors H-H interaction parameter eta, was evaluated for each isotherm. For both approximations a similar temperature dependence of eta(T) was obtained, with eta changing from attractive (i.e. negative) to repulsive (i.e. positive) with increasing isotherms temperatures. A good agreement was obtained between the calculated T-C values (derived from the eta(T) parameters) and the experimental observations. (C) 1998 Elsevier Science S.A. C1 Nucl Res Ctr Negev, IL-84190 Beer Sheva, Israel. Ben Gurion Univ Negev, IL-84105 Beer Sheva, Israel. Brookhaven Natl Lab, Upton, NY 11973 USA. RP Mintz, MH (reprint author), Nucl Res Ctr Negev, POB 9001, IL-84190 Beer Sheva, Israel. NR 30 TC 26 Z9 26 U1 0 U2 4 PU ELSEVIER SCIENCE SA PI LAUSANNE PA PO BOX 564, 1001 LAUSANNE, SWITZERLAND SN 0925-8388 J9 J ALLOY COMPD JI J. Alloy. Compd. PD MAR 6 PY 1998 VL 267 IS 1-2 BP 113 EP 120 DI 10.1016/S0925-8388(97)00521-5 PG 8 WC Chemistry, Physical; Materials Science, Multidisciplinary; Metallurgy & Metallurgical Engineering SC Chemistry; Materials Science; Metallurgy & Metallurgical Engineering GA ZE552 UT WOS:000072805000028 ER PT J AU Kalman, K Nguyen, A Tseng-Crank, J Dukes, ID Chandy, G Hustad, CM Copeland, NG Jenkins, NA Mohrenweiser, H Brandriff, B Cahalan, M Gutman, GA Chandy, KG AF Kalman, K Nguyen, A Tseng-Crank, J Dukes, ID Chandy, G Hustad, CM Copeland, NG Jenkins, NA Mohrenweiser, H Brandriff, B Cahalan, M Gutman, GA Chandy, KG TI Genomic organization, chromosomal localization, tissue distribution, and biophysical characterization of a novel mammalian Shaker-related voltage-gated potassium channel, Kv1.7 SO JOURNAL OF BIOLOGICAL CHEMISTRY LA English DT Article ID PANCREATIC BETA-CELLS; GENETIC-LINKAGE MAP; K+ CHANNELS; FUNCTIONAL EXPRESSION; NUCLEOTIDE-SEQUENCE; LEPTIN RECEPTOR; DROSOPHILA; ENCODES; FAMILY; MUSCLE AB We report the isolation of a novel mouse voltage-gated Shaker-related K+ channel gene, Kv1.7 (Kcna7/KCNA7). Unlike other known Kv1 family genes that have intronless coding regions, the protein-coding region of Ku1.7 is interrupted by a 1,9-kilobase pair intron, The Kv1.7 gene and the related Kv3.3 (Kcnc3/KCNC3) gene map to mouse chromosome 7 and human chromosome 19q13.3, a region that has been suggested to contain a diabetic susceptibility locus, The mouse Kv1,7 channel is voltage-dependent and rapidly inactivating, exhibits cumulative inactivation, and has a single channel conductance of 21 pS, It is potently blocked by noxiustoxin and stichodactylatoxin, and is insensitive to tetraethylammonium, kaliotoxin, and charybdotoxin. Northern blot analysis reveals similar to 3-kilobase pair Kv1.7 transcripts in mouse heart and skeletal muscle, In situ hybridization demonstrates the presence of Kv1.7 in mouse pancreatic islet cells. Kv1.7 was also isolated from mouse brain and hamster insulinoma cells by polymerase chain reaction. C1 Univ Calif Irvine, Sch Med, Dept Physiol & Biophys, Irvine, CA 92697 USA. Univ Calif Irvine, Dept Microbiol & Mol Genet, Irvine, CA 92697 USA. Glaxo Wellcome Res Inst, Res Triangle Pk, NC 27709 USA. NCI, Frederick Canc Res & Dev Ctr, ABL Basic Res Program, Mammalian Genet Lab, Frederick, MD 21702 USA. Univ Calif Lawrence Livermore Natl Lab, Ctr Human Genome, Livermore, CA 94550 USA. RP Chandy, KG (reprint author), Univ Calif Irvine, Sch Med, Dept Physiol & Biophys, Rm 291,Joan Irvine Simth Hall, Irvine, CA 92697 USA. EM gchandy@uci.edu FU NIAID NIH HHS [AI-24783]; NIGMS NIH HHS [GMOD54872]; NINDS NIH HHS [NS14609] NR 37 TC 53 Z9 54 U1 0 U2 1 PU AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC PI BETHESDA PA 9650 ROCKVILLE PIKE, BETHESDA, MD 20814 USA SN 0021-9258 J9 J BIOL CHEM JI J. Biol. Chem. PD MAR 6 PY 1998 VL 273 IS 10 BP 5851 EP 5857 DI 10.1074/jbc.273.10.5851 PG 7 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZA256 UT WOS:000072345000065 PM 9488722 ER PT J AU Drennen, TE Erickson, JD AF Drennen, TE Erickson, JD TI Policy: Energy - Who will fuel China? SO SCIENCE LA English DT Article C1 Sandia Natl Labs, Albuquerque, NM 87185 USA. Hobart & William Smith Coll, Dept Econ, Geneva, NY 14456 USA. Rensselaer Polytech Inst, Dept Econ, Troy, NY 12180 USA. RP Drennen, TE (reprint author), Sandia Natl Labs, POB 5800, Albuquerque, NM 87185 USA. RI Erickson, Jon/C-4020-2009 NR 8 TC 9 Z9 9 U1 0 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 6 PY 1998 VL 279 IS 5356 BP 1483 EP 1483 DI 10.1126/science.279.5356.1483 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZA527 UT WOS:000072372900048 ER PT J AU Perl, ML AF Perl, ML TI Image and logic. Material culture of microphysics SO SCIENCE LA English DT Book Review C1 Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. RP Perl, ML (reprint author), Stanford Univ, Stanford Linear Accelerator Ctr, Stanford, CA 94309 USA. NR 1 TC 0 Z9 0 U1 0 U2 1 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 6 PY 1998 VL 279 IS 5356 BP 1484 EP 1484 DI 10.1126/science.279.5356.1484 PG 1 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZA527 UT WOS:000072372900049 ER PT J AU Tang, WM AF Tang, WM TI Plasma physics - Connecting again with magnetic reconnection SO SCIENCE LA English DT Article C1 Princeton Univ, Princeton Plasma Phys Lab, Princeton, NJ 08543 USA. RP Tang, WM (reprint author), Princeton Univ, Princeton Plasma Phys Lab, POB 451, Princeton, NJ 08543 USA. NR 11 TC 5 Z9 5 U1 1 U2 2 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 6 PY 1998 VL 279 IS 5356 BP 1488 EP 1489 DI 10.1126/science.279.5356.1488 PG 2 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZA527 UT WOS:000072372900052 ER PT J AU Redinbo, MR Stewart, L Kuhn, P Champoux, JJ Hol, WGJ AF Redinbo, MR Stewart, L Kuhn, P Champoux, JJ Hol, WGJ TI Crystal structures of human topoisomerase I in covalent and noncovalent complexes with DNA SO SCIENCE LA English DT Article ID CAMPTOTHECIN RESISTANCE; CATALYTIC ACTIVITY; ANTITUMOR-ACTIVITY; TERMINAL FRAGMENT; EUKARYOTIC TOPOISOMERASE; CLEAVABLE COMPLEXES; POINT MUTATION; BINDING-SITE; WHEAT-GERM; IDENTIFICATION AB Topoisomerases I promote the relaxation of DNA superhelical tension by introducing a transient Single-stranded break in duplex DNA and are vital for the processes of replication, transcription, and recombination, The crystal structures at 2.1 and 2.5 angstrom resolution of reconstituted human topoisomerase I comprising the core and carboxyl-terminal domains in covalent and noncovalent complexes with 22-base pair DNA duplexes reveal an enzyme that "clamps" around essentially B-form DNA, The core domain and the first eight residues of the carboxyl-terminal domain of the enzyme, including the active-site nuleophile tyrosine-723, share significant structural similarity with the bacteriophage family of DNA integrases. A binding mode for the anticancer drug camptothecin is proposed on the basis of chemical and biochemical information combined with these three-dimensional structures of topoisomerase I-DNA complexes. C1 Univ Washington, Sch Med, Biomol Struct Ctr, Seattle, WA 98195 USA. Univ Washington, Sch Med, Dept Biol Struct, Seattle, WA 98195 USA. Stanford Univ, Stanford Synchrotron Radiat Lab, Stanford, CA 94309 USA. Univ Washington, Sch Med, Dept Microbiol, Seattle, WA 98195 USA. Univ Washington, Sch Med, Dept Biochem, Howard Hughes Med Inst, Seattle, WA 98195 USA. Univ Washington, Sch Med, Dept Biol Struct, Howard Hughes Med Inst, Seattle, WA 98195 USA. RP Hol, WGJ (reprint author), Univ Washington, Sch Med, Biomol Struct Ctr, Box 357742, Seattle, WA 98195 USA. FU NCI NIH HHS [CA65656]; NIGMS NIH HHS [GM49156] NR 75 TC 638 Z9 655 U1 8 U2 46 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 6 PY 1998 VL 279 IS 5356 BP 1504 EP 1513 DI 10.1126/science.279.5356.1504 PG 10 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZA527 UT WOS:000072372900057 PM 9488644 ER PT J AU Zhou, SJ Preston, DL Lomdahl, PS Beazley, DM AF Zhou, SJ Preston, DL Lomdahl, PS Beazley, DM TI Large-scale molecular dynamics simulations of dislocation intersection in copper SO SCIENCE LA English DT Article ID STRESS; ENERGY AB The results of massively parallel three-dimensional molecular dynamics simulations of the perpendicular intersection of extended dislocations in copper are reported. The intersection process, which involves three of the four possible {111} glide planes in the face-centered cubic lattice, begins with junction formation, followed by unzipping, partial dislocation bowing, cutting, and, finally, unit jog formation. The investigation provides insights into this complex atomistic process, which is currently not accessible to experimental investigation. C1 Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Zhou, SJ (reprint author), Univ Calif Los Alamos Natl Lab, Appl Theoret & Computat Phys Div, Los Alamos, NM 87545 USA. NR 23 TC 140 Z9 142 U1 4 U2 35 PU AMER ASSOC ADVANCEMENT SCIENCE PI WASHINGTON PA 1200 NEW YORK AVE, NW, WASHINGTON, DC 20005 USA SN 0036-8075 J9 SCIENCE JI Science PD MAR 6 PY 1998 VL 279 IS 5356 BP 1525 EP 1527 DI 10.1126/science.279.5356.1525 PG 3 WC Multidisciplinary Sciences SC Science & Technology - Other Topics GA ZA527 UT WOS:000072372900062 ER PT J AU Sun, M Lee, CS AF Sun, M Lee, CS TI Enzyme array amperometric detection in carbohydrate analysis SO BIOTECHNOLOGY AND BIOENGINEERING LA English DT Article DE enzyme array; pulsed amperometric detection; carbohydrate analysis ID EXOGLYCOSIDASE; DIGESTION AB The introduction of an enzyme array-electrochemical detection method for carbohydrate analysis is demonstrated by using two complex and one high mannose N-linked oligosaccharides. Instead of measuring the remaining uncleaved oligosaccharides in enzymatic digestion, released monosaccharides are directly quantified by pulsed amperometric detection at a gold electrode. The measured monosaccharide concentrations in combination with the enzyme array analysis provide structural characterization of oligosaccharides. The enzyme array-electrochemical detection method does not require any separation procedure or any prior labeling of oligosaccharides. However, this method is limited by the use of purified oligosaccharide samples and the nature of the enzyme array. The development of more sophisticated enzyme arrays relies upon the introduction of a bank of highly specific (bond, arm, aglycon) exoglycosidases. (C) 1998 John Wiley & Sons, Inc. C1 Iowa State Univ, US DOE, Dept Chem, Ames, IA 50011 USA. Iowa State Univ, US DOE, Ames Lab, Ames, IA 50011 USA. RP Lee, CS (reprint author), Iowa State Univ, US DOE, Dept Chem, Ames, IA 50011 USA. EM chenglee@iastate.edu NR 12 TC 2 Z9 2 U1 0 U2 0 PU WILEY-BLACKWELL PI MALDEN PA COMMERCE PLACE, 350 MAIN ST, MALDEN 02148, MA USA SN 0006-3592 J9 BIOTECHNOL BIOENG JI Biotechnol. Bioeng. PD MAR 5 PY 1998 VL 57 IS 5 BP 545 EP 551 PG 7 WC Biotechnology & Applied Microbiology SC Biotechnology & Applied Microbiology GA YT394 UT WOS:000071598600006 PM 10099233 ER PT J AU Mebel, AM Lin, MC Melius, CF AF Mebel, AM Lin, MC Melius, CF TI Rate constant of the HONO+HONO -> H2O+NO+NO2 reaction from ab initio MO and TST calculations SO JOURNAL OF PHYSICAL CHEMISTRY A LA English DT Article ID DENSITY-FUNCTIONAL THERMOCHEMISTRY; NITROUS-ACID; EXCHANGE; ENERGIES; MODEL AB Kinetics and mechanism for the bimolecular decomposition of HONO have been studied by ab initio molecular orbital (G2M) and transition-state theory calculations. The reaction can take place by the interaction of a cis and a trans isomer or two cis or two trans isomers, via four-, five-, and six-member ring transition states, with decreasing reaction barriers as the size of the ring increases. The lowest energy path with a 13.7 kcal/mol barrier was found to occur by the six-member ring TS1 formed by the reaction of cis- and trans-HONO. A similar six-member ring TS (TS2) formed by two cis isomers has a barrier height of 15.1 kcal/mol, which is very close to the 5-ring TS formed by two trans isomers, 15.7 kcal/mol. The total rate constant computed with the ab initio MO results, including the three reaction channels mentioned above and an additional channel involving a five-member ring TS formed by a cis-and a trans isomer with a 17.7 kcal/mol barrier, can be represented by the three-parameter expression for the 300-5000 K temperature range: k = 5.8 x 10(-25)T(3.64) exp(-6109/T) cm(3)/(molecule.s), which includes the Boltzmann-averaged contribution of the cis isomer. The theoretical value was found to be considerably lower than the available experimental results (which are believed to have suffered from deleterious surface effects). C1 Emory Univ, Dept Chem, Atlanta, GA 30322 USA. Sandia Natl Labs, Combust Res Facil, Livermore, CA 94552 USA. RP Lin, MC (reprint author), Emory Univ, Dept Chem, 1515 Pierce Dr, Atlanta, GA 30322 USA. RI Mebel, Alexander/A-5234-2009 NR 34 TC 33 Z9 33 U1 1 U2 4 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1089-5639 J9 J PHYS CHEM A JI J. Phys. Chem. A PD MAR 5 PY 1998 VL 102 IS 10 BP 1803 EP 1807 DI 10.1021/jp973449w PG 5 WC Chemistry, Physical; Physics, Atomic, Molecular & Chemical SC Chemistry; Physics GA ZB971 UT WOS:000072526700018 ER PT J AU Gole, JL Dixon, DA AF Gole, JL Dixon, DA TI Electrochemical methoxylation of an HF-etched porous silicon surface SO JOURNAL OF PHYSICAL CHEMISTRY B LA English DT Article ID LUMINESCENCE MECHANISM; MOLECULAR-STRUCTURE; BASIS-SETS; OXIDATION; SI; PHOTOLUMINESCENCE; ABSTRACTION; GEOMETRIES; PREDICTION; CHEMISTRY AB The electrochemical methoxylation of a porous silicon (PS) surface using an anhydrous methanol etch and the resulting modification of the photoluminescent emission (PL) from the surface are evaluated within the framework of the silanone-based silicon oxyhydride fluorophors and their methylated counterparts. The molecular electronic structure of the ground-state singlet and low-lying triplet electronic states of some 20 oxyhydrides of the form O=Si(R)(2), O=Si(R)OR, and O=Si(OR)(2), where R = H, CH3, or SiH3, is considered. The predicted electronic transitions correlate well with the experimentally observed PL for PS and its methoxylated counterpart. The substitution of a methyl (CH3) group for a silyl (SiH3) unit is predicted to produce the observed PL blue shift accompanied by an increased PL intensity and stability. C1 Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. Pacific NW Lab, Environm Mol Sci Lab, Richland, WA 99352 USA. RP Georgia Inst Technol, Sch Phys, Atlanta, GA 30332 USA. NR 51 TC 18 Z9 18 U1 0 U2 0 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 1520-6106 J9 J PHYS CHEM B JI J. Phys. Chem. B PD MAR 5 PY 1998 VL 102 IS 10 BP 1768 EP 1774 DI 10.1021/jp980140j PG 7 WC Chemistry, Physical SC Chemistry GA ZB972 UT WOS:000072526800018 ER PT J AU Blomqvist, KI Boeglin, WU Bohm, R Distler, M Edelhoff, R Friedrich, J Geiges, R Jones, MK Kahrau, M Korn, M Kramer, H Krygier, KW Kunde, V Kuss, M Liesenfeld, A Merle, K Morris, CL Neuhausen, R Offermann, EAJM Pospischil, T Potokar, M Ransome, RD Richter, AW Ritchie, BG Rokavec, A Rosner, G Ryckebusch, J Sauer, P Schardt, S Vodenik, B Wagner, A Walcher, T Wolf, S Yadav, MK AF Blomqvist, KI Boeglin, WU Bohm, R Distler, M Edelhoff, R Friedrich, J Geiges, R Jones, MK Kahrau, M Korn, M Kramer, H Krygier, KW Kunde, V Kuss, M Liesenfeld, A Merle, K Morris, CL Neuhausen, R Offermann, EAJM Pospischil, T Potokar, M Ransome, RD Richter, AW Ritchie, BG Rokavec, A Rosner, G Ryckebusch, J Sauer, P Schardt, S Vodenik, B Wagner, A Walcher, T Wolf, S Yadav, MK TI Investigation of short-range nucleon-nucleon correlations using the reaction C-12(e,e ' pp) in close to 4 pi geometry SO PHYSICS LETTERS B LA English DT Article DE short-range nucleon-nucleon correlations ID ELECTRON-SCATTERING; PHOTON-ABSORPTION; SPECTRAL-FUNCTION; DELTA-RESONANCE; E,E'P REACTION; GROUND-STATE; O-16; C-12; MECHANISM; KNOCKOUT AB Two-proton correlations were studied in close to 4 pi geometry using the reaction C-12(e,e' pp). The beam energy was 705 MeV, the energy transfer 225 MeV, and the three-momentum transfer 412 MeV/c. The electrons were observed in a large-acceptance magnetic spectrometer in coincidence with protons observed in a BGO crystal ball. Missing energy and momentum, relative momentum and angular distributions were derived and compared with a factorized two-nucleon emission model. Soft-core correlation functions are favoured by the data. (C) 1998 Elsevier Science B.V. C1 Univ Mainz, Inst Kernphys, D-55099 Mainz, Germany. TH Darmstadt, Inst Kernphys, D-64289 Darmstadt, Germany. Univ Calif Los Alamos Natl Lab, Div Phys, Los Alamos, NM 87545 USA. Univ Ljubljana, Jozef Stefan Inst, Ljubljana, Slovenia. Rutgers State Univ, Dept Phys & Astron, Piscataway, NJ 08855 USA. Arizona State Univ, Dept Phys & Astron, Tempe, AZ 85287 USA. State Univ Ghent, Dept Subatom & Radiat Phys, B-9000 Ghent, Belgium. RP Rosner, G (reprint author), Univ Mainz, Inst Kernphys, JJ Becher Weg 45, D-55099 Mainz, Germany. RI Kuss, Michael/H-8959-2012 NR 42 TC 36 Z9 36 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 5 PY 1998 VL 421 IS 1-4 BP 71 EP 78 DI 10.1016/S0370-2693(98)00024-0 PG 8 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK261 UT WOS:000073301500013 ER PT J AU Brisudova, MM Szpigel, S Perry, RJ AF Brisudova, MM Szpigel, S Perry, RJ TI Effects of massive gluons on quarkonia in light-front QCD SO PHYSICS LETTERS B LA English DT Article ID RENORMALIZATION-GROUP; HAMILTONIANS AB A constituent parton picture of hadrons with logarithmic confinement arises naturally in light-front QCD when the hamiltonian is computed using a perturbative renormalization group; however, rotational symmetry is not manifest as a simple kinematic symmetry. Relevant operators must typically be fine-tuned when a perturbative renormalization group is used, and in light-front field theory such operators contain functions of longitudinal moments. We explore the possibility that a gluon mass operator with simple longitudinal momentum dependence may improve approximate kinematic rotational symmetry, as revealed by the potential between heavy quarks. (C) 1998 Elsevier Science B.V. C1 Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Calif Los Alamos Natl Lab, Div Theoret, Los Alamos, NM 87545 USA. RP Brisudova, MM (reprint author), Ohio State Univ, Dept Phys, 174 W 18Th Ave, Columbus, OH 43210 USA. OI Szpigel, Sergio/0000-0003-2529-2225 NR 15 TC 8 Z9 8 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 5 PY 1998 VL 421 IS 1-4 BP 334 EP 340 DI 10.1016/S0370-2693(97)01556-6 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK261 UT WOS:000073301500048 ER PT J AU Breitweg, J Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Repond, J Stanek, R Talaga, RL Yoshida, R Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Gialas, I Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Ricci, F Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Katz, UF Kerger, R Paul, E Pfeiffer, M Rembser, C Stamm, J Wedemeyer, R Wieber, H Bailey, DS Campbell-Robson, S Cottingham, WN Foster, B Hall-Wilton, R Hayes, ME Heath, GP Heath, HF McFall, JD Piccioni, D Roff, DG Tapper, RJ Arneodo, M Ayad, R Capua, M Garfagnini, A Iannotti, L Schioppa, M Susinno, G Kim, JY Lee, JH Lim, IT Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sampson, S Sciulli, F Straub, PB Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Bukowy, M Jelen, K Kisielewska, D Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Cases, G Deppe, O Desler, K Drews, G Fricke, U Gilkinson, DJ Glasman, C Gottlicher, P Haas, T Hain, W Hasell, D Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Labs, J Lindemann, L Lohr, B Lowe, M Manczak, O Milewski, J Monteiro, T Ng, JST Notz, D Ohrenberg, K Park, IH Pellegrino, A Pelucchi, F Piotrzkowski, K Roco, M Rohde, M Roldan, J Ryan, JJ Savin, AA Schneekloth, U Selonke, F Surrow, B Tassi, E Voss, T Westphal, D Wolf, G Wollmer, U Youngman, C Zarnecki, AF Zeuner, W Burow, BD Grabosch, HJ Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Macdonald, N Saxon, DH Sinclair, LE Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Gladilin, LK Horstmann, D Kcira, D Klanner, R Lohrmann, E Poelz, G Schott, W Zetsche, F Bacon, TC Butterworth, I Cole, JE Howell, G Hung, BHY Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Walker, R Mallik, U Wang, SM Wu, JT Cloth, P Filges, D Fleck, JI Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Hong, SJ Lee, SB Nam, SW Park, SK Barreiro, F Fernandez, JP Garcia, G Graciani, R Hernandez, JM Hervas, L Labarga, L Martinez, M del Peso, J Puga, J Terron, J de Troconiz, JF Corriveau, F Hanna, DS Hartmann, J Hung, LW Murray, WN Ochs, A Riveline, M Stairs, DG St-Laurent, M Ullmann, R Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Chlebana, F Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Vreeswijk, M Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Romanowski, TA Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Nath, C Noyes, VA Quadt, A Ruske, O Tickner, JR Uijterwaal, H Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Bulmahn, J Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Rahn, JT Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Schwarzer, O Walenta, AH Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Hartner, GF Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Teuscher, RJ Butterworth, JM Catterall, CD Jones, TW Lane, SB Saunders, RL Sutton, MR Wing, M Ciborowski, J Grzelak, G Kasprzak, M Muchorowski, K Nowak, RJ Pawlak, JM Pawlak, R Tymieniecka, T Wroblewski, AK Zakrzewski, JA Adamus, M Coldewey, C Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Khakzad, M Schmidke, WB AF Breitweg, J Derrick, M Krakauer, D Magill, S Mikunas, D Musgrave, B Repond, J Stanek, R Talaga, RL Yoshida, R Zhang, H Mattingly, MCK Anselmo, F Antonioli, P Bari, G Basile, M Bellagamba, L Boscherini, D Bruni, A Bruni, G Romeo, GC Castellini, G Cifarelli, L Cindolo, F Contin, A Corradi, M De Pasquale, S Gialas, I Giusti, P Iacobucci, G Laurenti, G Levi, G Margotti, A Massam, T Nania, R Palmonari, F Pesci, A Polini, A Ricci, F Sartorelli, G Garcia, YZ Zichichi, A Amelung, C Bornheim, A Brock, I Coboken, K Crittenden, J Deffner, R Eckert, M Grothe, M Hartmann, H Heinloth, K Heinz, L Hilger, E Jakob, HP Katz, UF Kerger, R Paul, E Pfeiffer, M Rembser, C Stamm, J Wedemeyer, R Wieber, H Bailey, DS Campbell-Robson, S Cottingham, WN Foster, B Hall-Wilton, R Hayes, ME Heath, GP Heath, HF McFall, JD Piccioni, D Roff, DG Tapper, RJ Arneodo, M Ayad, R Capua, M Garfagnini, A Iannotti, L Schioppa, M Susinno, G Kim, JY Lee, JH Lim, IT Pac, MY Caldwell, A Cartiglia, N Jing, Z Liu, W Mellado, B Parsons, JA Ritz, S Sampson, S Sciulli, F Straub, PB Zhu, Q Borzemski, P Chwastowski, J Eskreys, A Figiel, J Klimek, K Przybycien, MB Zawiejski, L Adamczyk, L Bednarek, B Bukowy, M Jelen, K Kisielewska, D Kowalski, T Przybycien, M Rulikowska-Zarebska, E Suszycki, L Zajac, J Dulinski, Z Kotanski, A Abbiendi, G Bauerdick, LAT Behrens, U Beier, H Bienlein, JK Cases, G Deppe, O Desler, K Drews, G Fricke, U Gilkinson, DJ Glasman, C Gottlicher, P Haas, T Hain, W Hasell, D Johnson, KF Kasemann, M Koch, W Kotz, U Kowalski, H Labs, J Lindemann, L Lohr, B Lowe, M Manczak, O Milewski, J Monteiro, T Ng, JST Notz, D Ohrenberg, K Park, IH Pellegrino, A Pelucchi, F Piotrzkowski, K Roco, M Rohde, M Roldan, J Ryan, JJ Savin, AA Schneekloth, U Selonke, F Surrow, B Tassi, E Voss, T Westphal, D Wolf, G Wollmer, U Youngman, C Zarnecki, AF Zeuner, W Burow, BD Grabosch, HJ Meyer, A Schlenstedt, S Barbagli, G Gallo, E Pelfer, P Maccarrone, G Votano, L Bamberger, A Eisenhardt, S Markun, P Trefzger, T Wolfle, S Bromley, JT Brook, NH Bussey, PJ Doyle, AT Macdonald, N Saxon, DH Sinclair, LE Strickland, E Waugh, R Bohnet, I Gendner, N Holm, U Meyer-Larsen, A Salehi, H Wick, K Gladilin, LK Horstmann, D Kcira, D Klanner, R Lohrmann, E Poelz, G Schott, W Zetsche, F Bacon, TC Butterworth, I Cole, JE Howell, G Hung, BHY Lamberti, L Long, KR Miller, DB Pavel, N Prinias, A Sedgbeer, JK Sideris, D Walker, R Mallik, U Wang, SM Wu, JT Cloth, P Filges, D Fleck, JI Ishii, T Kuze, M Suzuki, I Tokushuku, K Yamada, S Yamauchi, K Yamazaki, Y Hong, SJ Lee, SB Nam, SW Park, SK Barreiro, F Fernandez, JP Garcia, G Graciani, R Hernandez, JM Hervas, L Labarga, L Martinez, M del Peso, J Puga, J Terron, J de Troconiz, JF Corriveau, F Hanna, DS Hartmann, J Hung, LW Murray, WN Ochs, A Riveline, M Stairs, DG St-Laurent, M Ullmann, R Tsurugai, T Bashkirov, V Dolgoshein, BA Stifutkin, A Bashindzhagyan, GL Ermolov, PF Golubkov, YA Khein, LA Korotkova, NA Korzhavina, IA Kuzmin, VA Lukina, OY Proskuryakov, AS Shcheglova, LM Solomin, AN Zotkin, SA Bokel, C Botje, M Brummer, N Chlebana, F Engelen, J Koffeman, E Kooijman, P van Sighem, A Tiecke, H Tuning, N Verkerke, W Vossebeld, J Vreeswijk, M Wiggers, L de Wolf, E Acosta, D Bylsma, B Durkin, LS Gilmore, J Ginsburg, CM Kim, CL Ling, TY Nylander, P Romanowski, TA Blaikley, HE Cashmore, RJ Cooper-Sarkar, AM Devenish, RCE Edmonds, JK Grosse-Knetter, J Harnew, N Nath, C Noyes, VA Quadt, A Ruske, O Tickner, JR Uijterwaal, H Walczak, R Waters, DS Bertolin, A Brugnera, R Carlin, R Dal Corso, F Dosselli, U Limentani, S Morandin, M Posocco, M Stanco, L Stroili, R Voci, C Bulmahn, J Oh, BY Okrasinski, JR Toothacker, WS Whitmore, JJ Iga, Y D'Agostini, G Marini, G Nigro, A Raso, M Hart, JC McCubbin, NA Shah, TP Epperson, D Heusch, C Rahn, JT Sadrozinski, HFW Seiden, A Wichmann, R Williams, DC Schwarzer, O Walenta, AH Abramowicz, H Briskin, G Dagan, S Kananov, S Levy, A Abe, T Fusayasu, T Inuzuka, M Nagano, K Umemori, K Yamashita, T Hamatsu, R Hirose, T Homma, K Kitamura, S Matsushita, T Cirio, R Costa, M Ferrero, MI Maselli, S Monaco, V Peroni, C Petrucci, MC Ruspa, M Sacchi, R Solano, A Staiano, A Dardo, M Bailey, DC Fagerstroem, CP Galea, R Hartner, GF Joo, KK Levman, GM Martin, JF Orr, RS Polenz, S Sabetfakhri, A Simmons, D Teuscher, RJ Butterworth, JM Catterall, CD Jones, TW Lane, SB Saunders, RL Sutton, MR Wing, M Ciborowski, J Grzelak, G Kasprzak, M Muchorowski, K Nowak, RJ Pawlak, JM Pawlak, R Tymieniecka, T Wroblewski, AK Zakrzewski, JA Adamus, M Coldewey, C Eisenberg, Y Hochman, D Karshon, U Badgett, WF Chapin, D Cross, R Dasu, S Foudas, C Loveless, RJ Mattingly, S Reeder, DD Smith, WH Vaiciulis, A Wodarczyk, M Deshpande, A Dhawan, S Hughes, VW Bhadra, S Frisken, WR Khakzad, M Schmidke, WB CA ZEUS Collaboration TI Event shape analysis of deep inelastic scattering events with a large rapidity gap at HERA SO PHYSICS LETTERS B LA English DT Article ID LUND MONTE-CARLO; ELECTRON-POSITRON-ANNIHILATION; CENTRAL TRACKING DETECTOR; ZEUS BARREL CALORIMETER; E+E ANNIHILATION; DIFFRACTIVE SCATTERING; GLUON BREMSSTRAHLUNG; JET FRAGMENTATION; POMERON STRUCTURE; HADRON PRODUCTION AB A global event shape analysis of the multihadronic final states observed in neutral current deep inelastic scattering events with a large rapidity gap with respect to the proton direction is presented. The analysis is performed in the range 5 less than or equal to Q(2) less than or equal to 185 GeV2 and 160 less than or equal to W less than or equal to 250 GeV, where Q(2) is the virtuality of the photon and W is the virtual-photon proton centre of mass energy. Particular emphasis is placed on the dependence of the shape variables, measured in the gamma*-pomeron rest frame, on the mass of the hadronic final state, M-X. With increasing M-X the multihadronic final state becomes more collimated and planar. The experimental results are compared with several models which attempt to describe diffractive events. The broadening effects exhibited by the data require in these models a significant gluon component of the pomeron. (C) 1998 Elsevier Science B.V. C1 Argonne Natl Lab, Argonne, IL 60439 USA. Andrews Univ, Berrien Springs, MI 49104 USA. Univ Bologna, Bologna, Italy. Ist Nazl Fis Nucl, I-40126 Bologna, Italy. Univ Bonn, Inst Phys, D-5300 Bonn, Germany. Univ Bristol, HH Wills Phys Lab, Bristol BS8 1TL, Avon, England. Univ Calabria, Dept Phys, I-87036 Cosenza, Italy. INFN, I-87036 Cosenza, Italy. Chonnam Natl Univ, Kwangju, South Korea. Columbia Univ, Nevis Labs, Hudson, NY USA. Inst Nucl Phys, Krakow, Poland. Acad Min & Met, Fac Phys & Nucl Tech, Krakow, Poland. Jagiellonian Univ, Dept Phys, Krakow, Poland. DESY, D-2000 Hamburg, Germany. DESY IfH, Zeuthen, Germany. Univ Florence, Florence, Italy. Ist Nazl Fis Nucl, I-50125 Florence, Italy. Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy. Univ Freiburg, Fak Phys, D-7800 Freiburg Im Breisgau, Germany. Univ Glasgow, Dept Phys & Astron, Glasgow, Lanark, Scotland. Univ Hamburg, Inst Exp Phys 1, Hamburg, Germany. Univ Hamburg, Inst Expt Phys 2, D-2000 Hamburg, Germany. Univ London Imperial Coll Sci Technol & Med, High Energy Nucl Phys Grp, London, England. Univ Iowa, Dept Phys & Astron, Iowa City, IA 52242 USA. Forschungszentrum Julich, Inst Kernphys, D-5170 Julich, Germany. KEK, Inst Particle & Nucl Studies, Tsukuba, Ibaraki, Japan. Korea Univ, Seoul 136701, South Korea. Univ Autonoma Madrid, Dept Fis Teor, Madrid, Spain. McGill Univ, Dept Phys, Montreal, PQ, Canada. Meiji Gakuin Univ, Fac Gen Educ, Yokohama, Kanagawa, Japan. Moscow Engn Phys Inst, Moscow 115409, Russia. Moscow MV Lomonosov State Univ, Inst Nucl Phys, Moscow, Russia. NIKHEF H, NL-1009 DB Amsterdam, Netherlands. Univ Amsterdam, Amsterdam, Netherlands. Ohio State Univ, Dept Phys, Columbus, OH 43210 USA. Univ Oxford, Dept Phys, Oxford, England. Univ Padua, Dipartimento Fis, Padua, Italy. Ist Nazl Fis Nucl, Padua, Italy. Penn State Univ, Dept Phys, University Pk, PA 16802 USA. Polytech Univ, Sagamihara, Kanagawa, Japan. Univ Roma La Sapienza, Dipartimento Fis, I-00185 Rome, Italy. Ist Nazl Fis Nucl, Rome, Italy. Rutherford Appleton Lab, Didcot OX11 0QX, Oxon, England. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Siegen, Fachbereich Phys, D-5900 Siegen, Germany. Tel Aviv Univ, Raymond & Beverly Sackler Fac Exact Sci, Sch Phys, IL-69978 Tel Aviv, Israel. Univ Tokyo, Dept Phys, Tokyo 113, Japan. Tokyo Metropolitan Univ, Dept Phys, Tokyo, Japan. Univ Turin, Dipartimento Fis Sperimentale, Turin, Italy. Ist Nazl Fis Nucl, I-10125 Turin, Italy. Univ Torino, Fac Sci 2, Alessandria, Italy. INFN, Alessandria, Italy. Univ Toronto, Dept Phys, Toronto, ON, Canada. UCL, Dept Phys & Astron, London, England. Warsaw Univ, Inst Expt Phys, Warsaw, Poland. Inst Nucl Studies, PL-00681 Warsaw, Poland. Weizmann Inst Sci, Dept Particle Phys, IL-76100 Rehovot, Israel. Univ Wisconsin, Dept Phys, Madison, WI 53706 USA. Yale Univ, Dept Phys, New Haven, CT USA. York Univ, Dept Phys, N York, ON M3J 1P3, Canada. CNR, IROE, I-50127 Florence, Italy. RP Argonne Natl Lab, 9700 S Cass Ave, Argonne, IL 60439 USA. RI De Pasquale, Salvatore/B-9165-2008; Wing, Matthew/C-2169-2008; Bashkirov, Vladimir/A-4818-2008; Doyle, Anthony/C-5889-2009; Golubkov, Yury/E-1643-2012; Proskuryakov, Alexander/J-6166-2012; Katz, Uli/E-1925-2013; Wiggers, Leo/B-5218-2015; Tassi, Enrico/K-3958-2015; Gladilin, Leonid/B-5226-2011; Morandin, Mauro/A-3308-2016; Solomin, Anatoly/C-3072-2016; Hernandez Calama, Jose Maria/H-9127-2015; Capua, Marcella/A-8549-2015; OI De Pasquale, Salvatore/0000-0001-9236-0748; Doyle, Anthony/0000-0001-6322-6195; Katz, Uli/0000-0002-7063-4418; Wiggers, Leo/0000-0003-1060-0520; Gladilin, Leonid/0000-0001-9422-8636; Morandin, Mauro/0000-0003-4708-4240; Hernandez Calama, Jose Maria/0000-0001-6436-7547; Bailey, David C/0000-0002-7970-7839; Castellini, Guido/0000-0002-0177-0643; Kasemann, Matthias/0000-0002-0429-2448; Capua, Marcella/0000-0002-2443-6525; Arneodo, Michele/0000-0002-7790-7132; Abbiendi, Giovanni/0000-0003-4499-7562; Graciani Diaz, Ricardo/0000-0001-7166-5198 NR 66 TC 30 Z9 30 U1 0 U2 4 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 EI 1873-2445 J9 PHYS LETT B JI Phys. Lett. B PD MAR 5 PY 1998 VL 421 IS 1-4 BP 368 EP 384 DI 10.1016/S0370-2693(97)01539-6 PG 17 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK261 UT WOS:000073301500053 ER PT J AU Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NJ Cremaldi, LM Darling, C Denisenko, K Fernandez, A Fox, G Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yi, D Yoshida, S Zaliznyak, R Zhang, C AF Aitala, EM Amato, S Anjos, JC Appel, JA Ashery, D Banerjee, S Bediaga, I Blaylock, G Bracker, SB Burchat, PR Burnstein, RA Carter, T Carvalho, HS Copty, NJ Cremaldi, LM Darling, C Denisenko, K Fernandez, A Fox, G Gagnon, P Gobel, C Gounder, K Halling, AM Herrera, G Hurvits, G James, C Kasper, PA Kwan, S Langs, DC Leslie, J Lundberg, B MayTal-Beck, S Meadows, B Neto, JRTD Milburn, RH de Miranda, JM Napier, A Nguyen, A d'Oliveira, AB O'Shaughnessy, K Peng, KC Perera, LP Purohit, MV Quinn, B Radeztsky, S Rafatian, A Reay, NW Reidy, JJ dos Reis, AC Rubin, HA Sanders, DA Santha, AKS Santoro, AFS Schwartz, AJ Sheaff, M Sidwell, RA Slaughter, AJ Sokoloff, MD Solano, J Stanton, NR Stenson, K Summers, DJ Takach, S Thorne, K Tripathi, AK Watanabe, S Weiss-Babai, R Wiener, J Witchey, N Wolin, E Yi, D Yoshida, S Zaliznyak, R Zhang, C CA Fermilab E791 Collaboration TI Branching fractions for D-0 -> K+K- and D-0 ->pi(+)pi(-), and a search for CP violation in D-0 decays SO PHYSICS LETTERS B LA English DT Article ID CABIBBO-SUPPRESSED DECAYS; FINAL-STATE INTERACTIONS; SU(3); MESON; D0->PI-PI+; D0->K-K+; SYSTEM; D+ AB Using the large hadroproduced charm sample collected in experiment E791 at Fermilab, we have measured ratios of branching fractions for the two-body singly-Cabibbo-suppres sed charged decays of the D-0* Gamma(D-0 --> K+ K-)/Gamma(D0 --> K- pi(+)) = 0.109 +/- 0.003 +/- 0.003 Gamma(D-0--> K+K-)/Gamma(D0 --> K-K+) = 0.040 +/- 0.002 +/- 0.003, and Gamma(D0 --> K+K-)/Gamma(D-0 --> pi(+)pi(-)) = 2.75 +/- 0.15 +/- 0.16. We have looked for differences in the decay rates of D-0 and (D) over bar(-0) to the CP eigenstates K+K- and pi(+)pi(-), and have measured the CP asymmetry parameters A(CP)(K+ K-) = -0.010 +/- 0.049 +/- 0.012 and A(CP)(pi(+) pi(-)) = -0.049 +/- 0.078 +/- 0.030, both consistent with zero. (C) 1998 Elsevier Science B.V. C1 Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. Univ Calif Santa Cruz, Santa Cruz, CA 95064 USA. Univ Cincinnati, Cincinnati, OH 45221 USA. CINVESTAV, Mexico City 14000, DF, Mexico. Fermilab, Batavia, IL 60510 USA. IIT, Chicago, IL 60616 USA. Kansas State Univ, Manhattan, KS 66506 USA. Univ Massachusetts, Amherst, MA 01003 USA. Univ Mississippi, University, MS 38677 USA. Ohio State Univ, Columbus, OH 43210 USA. Princeton Univ, Princeton, NJ 08544 USA. Univ Autonoma Puebla, Mexico City, DF, Mexico. Univ S Carolina, Columbia, SC 29208 USA. Stanford Univ, Stanford, CA 94305 USA. Tel Aviv Univ, IL-69978 Tel Aviv, Israel. Tufts Univ, Medford, MA 02155 USA. Univ Wisconsin, Madison, WI 53706 USA. Yale Univ, New Haven, CT 06511 USA. RP Aitala, EM (reprint author), Ctr Brasileiro Pesquisas Fis, Rio De Janeiro, Brazil. RI Anjos, Joao/C-8335-2013; Gobel Burlamaqui de Mello, Carla /H-4721-2016; de Mello Neto, Joao/C-5822-2013 OI Gobel Burlamaqui de Mello, Carla /0000-0003-0523-495X; de Mello Neto, Joao/0000-0002-3234-6634 NR 37 TC 33 Z9 33 U1 0 U2 0 PU ELSEVIER SCIENCE BV PI AMSTERDAM PA PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS SN 0370-2693 J9 PHYS LETT B JI Phys. Lett. B PD MAR 5 PY 1998 VL 421 IS 1-4 BP 405 EP 411 DI 10.1016/S0370-2693(97)01570-0 PG 7 WC Astronomy & Astrophysics; Physics, Nuclear; Physics, Particles & Fields SC Astronomy & Astrophysics; Physics GA ZK261 UT WOS:000073301500056 ER PT J AU Zhang, ZJ Wang, ZL Chakoumakos, BC Yin, JS AF Zhang, ZJ Wang, ZL Chakoumakos, BC Yin, JS TI Temperature dependence of cation distribution and oxidation state in magnetic Mn-Fe ferrite nanocrystals SO JOURNAL OF THE AMERICAN CHEMICAL SOCIETY LA English DT Article ID NANOSCALE MNFE2O4 PARTICLES; FINE PARTICLES; CURIE-TEMPERATURE; SIZE; COPRECIPITATION; OXIDES; 3D AB The magnetic properties of spinel nanoparticles are determined by crystal chemistry issues such as cation distribution and oxidation states. The cation distribution and oxidation state of Mn-Fe spinel nanoparticles have been systematically studied at various temperatures by using neutron diffraction and electron energy loss spectroscopy, respectively. The Mn-Fe spinel nanoparticles prepared by coprecipitation have a high degree of inversion with 61% of the tetrahedral sites occupied by Fe3+ cations. The degree of inversion correlates with the distribution expected from random occupancy of cations consisting of Fe (60%) and Mn (40%). After heat treatment in a vacuum, the cation distribution reaches an equilibrium state with a 29% inversion. Initially. one-half of the Mn cations are in the +3 oxidation state and the other half are in the +2 oxidation state. Mn3+ cations are slowly and irreversibly reduced to Mn2+ with increasing temperature. When the temperature approaches 600 degrees C, all Mn cations are in the +2 state. These results provide direct evidence for the temperature-dependent change of crystal chemistry in Mn-Fe spinel nanoparticles, which has been closely related with the controversy on attributing the changes in the magnetic properties of the nanoparticles to crystallite size effect. These results will also provide an understanding of how to control crystal chemistry in order to control the properties of these magnetic nanoparticles. C1 Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. Georgia Inst Technol, Sch Mat Sci & Engn, Atlanta, GA 30332 USA. Oak Ridge Natl Lab, Div Solid State, Oak Ridge, TN 37831 USA. RP Zhang, ZJ (reprint author), Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA. RI Wang, Zhong Lin/E-2176-2011; Chakoumakos, Bryan/A-5601-2016 OI Wang, Zhong Lin/0000-0002-5530-0380; Chakoumakos, Bryan/0000-0002-7870-6543 NR 36 TC 168 Z9 171 U1 6 U2 50 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0002-7863 J9 J AM CHEM SOC JI J. Am. Chem. Soc. PD MAR 4 PY 1998 VL 120 IS 8 BP 1800 EP 1804 DI 10.1021/ja973085l PG 5 WC Chemistry, Multidisciplinary SC Chemistry GA ZA491 UT WOS:000072368600019 ER PT J AU Li, JL Gilroy, D Tiede, DM Gunner, MR AF Li, JL Gilroy, D Tiede, DM Gunner, MR TI Kinetic phases in the electron transfer from P(+)Q(A)(-)Q(B) to P(+)Q(A)Q(B)(-) and the associated processes in Rhodobacter sphaeroides R-26 reaction centers SO BIOCHEMISTRY LA English DT Article ID PHOTOSYNTHETIC REACTION CENTERS; BACTERIAL REACTION CENTERS; REACTION-CENTER PROTEIN; FTIR DIFFERENCE SPECTROSCOPY; RESOLVED INFRARED-SPECTROSCOPY; CHARGE RECOMBINATION KINETICS; RHODOPSEUDOMONAS-VIRIDIS; PROTON-TRANSFER; FREE-ENERGY; SECONDARY QUINONE AB Electron transfer from p(+)Q(A)(-)Q(B) to form p(+)Q(A)Q(B)(-) was measured in Rhodobacter sphaeroides R-26 reaction centers (RCs) where the native primary quinone, ubiquinone-10 (UQ(A)), was replaced by 2-methyl-3-phytyl-1,4-naphthoquinone (MQ(A)) The native secondary quinone, UQ-10, was retained as UQ(B) The difference spectrum of the semiquinone MQ(A)(-) minus UQ(B)(-) absorption is very similar to that of MQ(-) minus UQ(-) in solution (398-480 nm). Thus, the absorption change provides a direct monitor of the electron transfer from MQ(A)(-) to UQ(B) In contrast, when both Q(A) and Q(B) are UQ-10 the spectral difference between UQ(A)(-) and UQ(B)(-) arises from electrochromic responses of RC chromophores. Three kinetic processes are seen in the near UV (390-480 nm) and near-IR (740-820 nm). Analysis of the time-correlated spectra support the conclusion that the changes at tau(1) approximate to 3 mu s are mostly due to electron transfer, electron transfer and charge compensation are mixed in tau(2) approximate to 80 mu s, while little or no electron transfer occurs at 200-600 mu s (tau(3)) in MQ(A)UQ(B) RCs. The 80-mu s rate has been previously observed, while the fast component has not. The fast phase represents 60% of the electron-transfer reaction (398 nm). The activation energy for electron transfer is Delta G approximate to 3.5 kcal/mol for bath tau(1) and tau(2) between 0 and 30 degrees C. In isolated RCs with UQ(A), if there is any fast component, it appears to be faster and less important than in the MQ(A) reconstituted RCs. C1 CUNY City Coll, Dept Phys, New York, NY 10031 USA. Argonne Natl Lab, Chem Div D200, Argonne, IL 60439 USA. RP Gunner, MR (reprint author), CUNY City Coll, Dept Phys, Room J419,138th St & Convent Ave, New York, NY 10031 USA. EM gunner@scisun.sci.ccny.cuny.edu FU NIGMS NIH HHS [R01-GM48726] NR 82 TC 87 Z9 93 U1 1 U2 3 PU AMER CHEMICAL SOC PI WASHINGTON PA 1155 16TH ST, NW, WASHINGTON, DC 20036 USA SN 0006-2960 J9 BIOCHEMISTRY-US JI Biochemistry PD MAR 3 PY 1998 VL 37 IS 9 BP 2818 EP 2829 DI 10.1021/bi971699x PG 12 WC Biochemistry & Molecular Biology SC Biochemistry & Molecular Biology GA ZB940 UT WOS:000072523600013 PM 9485433 ER EF